diff --git a/scripts/update-fixtures.ts b/scripts/update-fixtures.ts
index b7ecc12..27715ff 100644
--- a/scripts/update-fixtures.ts
+++ b/scripts/update-fixtures.ts
@@ -53,6 +53,8 @@ for (const filename of Object.keys(Visitor.fixturesData)) {
             onExpressionCharacterClassEnter: enter,
             onFlagsEnter: enter,
             onGroupEnter: enter,
+            onModifierFlagsEnter: enter,
+            onModifiersEnter: enter,
             onPatternEnter: enter,
             onQuantifierEnter: enter,
             onRegExpLiteralEnter: enter,
@@ -71,6 +73,8 @@ for (const filename of Object.keys(Visitor.fixturesData)) {
             onExpressionCharacterClassLeave: leave,
             onFlagsLeave: leave,
             onGroupLeave: leave,
+            onModifierFlagsLeave: leave,
+            onModifiersLeave: leave,
             onPatternLeave: leave,
             onQuantifierLeave: leave,
             onRegExpLiteralLeave: leave,
diff --git a/src/ast.ts b/src/ast.ts
index 6628567..75fed3e 100644
--- a/src/ast.ts
+++ b/src/ast.ts
@@ -17,6 +17,7 @@ export type BranchNode =
     | ExpressionCharacterClass
     | Group
     | LookaroundAssertion
+    | Modifiers
     | Pattern
     | Quantifier
     | RegExpLiteral
@@ -31,6 +32,7 @@ export type LeafNode =
     | Character
     | CharacterSet
     | Flags
+    | ModifierFlags
 
 /**
  * The type which includes all atom nodes.
@@ -122,6 +124,7 @@ export interface Alternative extends NodeBase {
 export interface Group extends NodeBase {
     type: "Group"
     parent: Alternative | Quantifier
+    modifiers: Modifiers | null
     alternatives: Alternative[]
 }
 
@@ -446,6 +449,36 @@ export interface UnambiguousBackreference extends BaseBackreference {
     resolved: CapturingGroup
 }
 
+/**
+ * The modifiers.
+ */
+export interface Modifiers extends NodeBase {
+    type: "Modifiers"
+    parent: Group
+    /**
+     * The add modifier flags.
+     */
+    add: ModifierFlags
+    /**
+     * The remove modifier flags.
+     *
+     * `null` means no remove modifier flags. e.g. `(?ims:x)`
+     * The reason for `null` is that there is no position where the remove modifier flags appears. Must be behind the minus mark.
+     */
+    remove: ModifierFlags | null
+}
+
+/**
+ * The modifier flags.
+ */
+export interface ModifierFlags extends NodeBase {
+    type: "ModifierFlags"
+    parent: Modifiers
+    dotAll: boolean
+    ignoreCase: boolean
+    multiline: boolean
+}
+
 /**
  * The flags.
  */
diff --git a/src/parser.ts b/src/parser.ts
index 61522af..9f25b59 100644
--- a/src/parser.ts
+++ b/src/parser.ts
@@ -18,6 +18,7 @@ import type {
     UnicodeSetsCharacterClass,
     ExpressionCharacterClass,
     StringAlternative,
+    Modifiers,
 } from "./ast"
 import type { EcmaVersion } from "./ecma-versions"
 import { latestEcmaVersion } from "./ecma-versions"
@@ -31,6 +32,7 @@ type AppendableNode =
     | ClassStringDisjunction
     | Group
     | LookaroundAssertion
+    | Modifiers
     | Pattern
     | StringAlternative
 
@@ -205,14 +207,17 @@ class RegExpParserState {
             throw new Error("UnknownError")
         }
 
-        this._node = {
+        const group: Group = {
             type: "Group",
             parent,
             start,
             end: start,
             raw: "",
+            modifiers: null,
             alternatives: [],
         }
+
+        this._node = group
         parent.elements.push(this._node)
     }
 
@@ -227,6 +232,85 @@ class RegExpParserState {
         this._node = node.parent
     }
 
+    public onModifiersEnter(start: number): void {
+        const parent = this._node
+        if (parent.type !== "Group") {
+            throw new Error("UnknownError")
+        }
+
+        this._node = {
+            type: "Modifiers",
+            parent,
+            start,
+            end: start,
+            raw: "",
+            add: null as never, // Set in onAddModifiers.
+            remove: null,
+        }
+        parent.modifiers = this._node
+    }
+
+    public onModifiersLeave(start: number, end: number): void {
+        const node = this._node
+        if (node.type !== "Modifiers" || node.parent.type !== "Group") {
+            throw new Error("UnknownError")
+        }
+
+        node.end = end
+        node.raw = this.source.slice(start, end)
+        this._node = node.parent
+    }
+
+    public onAddModifiers(
+        start: number,
+        end: number,
+        {
+            ignoreCase,
+            multiline,
+            dotAll,
+        }: { ignoreCase: boolean; multiline: boolean; dotAll: boolean },
+    ): void {
+        const parent = this._node
+        if (parent.type !== "Modifiers") {
+            throw new Error("UnknownError")
+        }
+        parent.add = {
+            type: "ModifierFlags",
+            parent,
+            start,
+            end,
+            raw: this.source.slice(start, end),
+            ignoreCase,
+            multiline,
+            dotAll,
+        }
+    }
+
+    public onRemoveModifiers(
+        start: number,
+        end: number,
+        {
+            ignoreCase,
+            multiline,
+            dotAll,
+        }: { ignoreCase: boolean; multiline: boolean; dotAll: boolean },
+    ): void {
+        const parent = this._node
+        if (parent.type !== "Modifiers") {
+            throw new Error("UnknownError")
+        }
+        parent.remove = {
+            type: "ModifierFlags",
+            parent,
+            start,
+            end,
+            raw: this.source.slice(start, end),
+            ignoreCase,
+            multiline,
+            dotAll,
+        }
+    }
+
     public onCapturingGroupEnter(start: number, name: string | null): void {
         const parent = this._node
         if (parent.type !== "Alternative") {
@@ -765,7 +849,7 @@ export namespace RegExpParser {
          * - `2022` added `d` flag.
          * - `2023` added more valid Unicode Property Escapes.
          * - `2024` added `v` flag.
-         * - `2025` added duplicate named capturing groups.
+         * - `2025` added duplicate named capturing groups, modifiers.
          */
         ecmaVersion?: EcmaVersion
     }
diff --git a/src/validator.ts b/src/validator.ts
index 72c5439..6417ab5 100644
--- a/src/validator.ts
+++ b/src/validator.ts
@@ -1,3 +1,4 @@
+import type { Flags } from "./ast"
 import type { EcmaVersion } from "./ecma-versions"
 import { latestEcmaVersion } from "./ecma-versions"
 import type { GroupSpecifiers } from "./group-specifiers"
@@ -160,6 +161,24 @@ const CLASS_SET_RESERVED_PUNCTUATOR = new Set([
     TILDE,
 ])
 
+const FLAG_PROP_TO_CODEPOINT = {
+    global: LATIN_SMALL_LETTER_G,
+    ignoreCase: LATIN_SMALL_LETTER_I,
+    multiline: LATIN_SMALL_LETTER_M,
+    unicode: LATIN_SMALL_LETTER_U,
+    sticky: LATIN_SMALL_LETTER_Y,
+    dotAll: LATIN_SMALL_LETTER_S,
+    hasIndices: LATIN_SMALL_LETTER_D,
+    unicodeSets: LATIN_SMALL_LETTER_V,
+} as const
+const FLAG_CODEPOINT_TO_PROP: Record<FlagCodePoint, FlagProp> =
+    Object.fromEntries(
+        Object.entries(FLAG_PROP_TO_CODEPOINT).map(([k, v]) => [v, k]),
+    ) as never
+type FlagProp = keyof typeof FLAG_PROP_TO_CODEPOINT
+type FlagCodePoint = (typeof FLAG_PROP_TO_CODEPOINT)[FlagProp]
+type FlagsRecord = Omit<Flags, "end" | "parent" | "raw" | "start" | "type">
+
 function isSyntaxCharacter(cp: number): boolean {
     // ^ $ \ . * + ? ( ) [ ] { } |
     return SYNTAX_CHARACTER.has(cp)
@@ -218,6 +237,20 @@ function isUnicodePropertyValueCharacter(cp: number): boolean {
     return isUnicodePropertyNameCharacter(cp) || isDecimalDigit(cp)
 }
 
+/**
+ * ```
+ * RegularExpressionModifier :: one of
+ *   `i` `m` `s`
+ * ```
+ */
+function isRegularExpressionModifier(ch: number): boolean {
+    return (
+        ch === LATIN_SMALL_LETTER_I ||
+        ch === LATIN_SMALL_LETTER_M ||
+        ch === LATIN_SMALL_LETTER_S
+    )
+}
+
 export type RegExpValidatorSourceContext = {
     readonly source: string
     readonly start: number
@@ -244,7 +277,7 @@ export namespace RegExpValidator {
          * - `2022` added `d` flag.
          * - `2023` added more valid Unicode Property Escapes.
          * - `2024` added `v` flag.
-         * - `2025` added duplicate named capturing groups.
+         * - `2025` added duplicate named capturing groups, modifiers.
          */
         ecmaVersion?: EcmaVersion
 
@@ -368,6 +401,57 @@ export namespace RegExpValidator {
          */
         onGroupLeave?: (start: number, end: number) => void
 
+        /**
+         * A function that is called when the validator entered a modifiers.
+         * @param start The 0-based index of the first character.
+         */
+        onModifiersEnter?: (start: number) => void
+
+        /**
+         * A function that is called when the validator left a modifiers.
+         * @param start The 0-based index of the first character.
+         * @param end The next 0-based index of the last character.
+         */
+        onModifiersLeave?: (start: number, end: number) => void
+
+        /**
+         * A function that is called when the validator found an add modifiers.
+         * @param start The 0-based index of the first character.
+         * @param end The next 0-based index of the last character.
+         * @param flags flags.
+         * @param flags.ignoreCase `i` flag.
+         * @param flags.multiline `m` flag.
+         * @param flags.dotAll `s` flag.
+         */
+        onAddModifiers?: (
+            start: number,
+            end: number,
+            flags: {
+                ignoreCase: boolean
+                multiline: boolean
+                dotAll: boolean
+            },
+        ) => void
+
+        /**
+         * A function that is called when the validator found a remove modifiers.
+         * @param start The 0-based index of the first character.
+         * @param end The next 0-based index of the last character.
+         * @param flags flags.
+         * @param flags.ignoreCase `i` flag.
+         * @param flags.multiline `m` flag.
+         * @param flags.dotAll `s` flag.
+         */
+        onRemoveModifiers?: (
+            start: number,
+            end: number,
+            flags: {
+                ignoreCase: boolean
+                multiline: boolean
+                dotAll: boolean
+            },
+        ) => void
+
         /**
          * A function that is called when the validator entered a capturing group.
          * @param start The 0-based index of the first character.
@@ -786,68 +870,8 @@ export class RegExpValidator {
         start: number,
         end: number,
     ): void {
-        const existingFlags = new Set<number>()
-        let global = false
-        let ignoreCase = false
-        let multiline = false
-        let sticky = false
-        let unicode = false
-        let dotAll = false
-        let hasIndices = false
-        let unicodeSets = false
-        for (let i = start; i < end; ++i) {
-            const flag = source.charCodeAt(i)
-
-            if (existingFlags.has(flag)) {
-                this.raise(`Duplicated flag '${source[i]}'`, { index: start })
-            }
-            existingFlags.add(flag)
-
-            if (flag === LATIN_SMALL_LETTER_G) {
-                global = true
-            } else if (flag === LATIN_SMALL_LETTER_I) {
-                ignoreCase = true
-            } else if (flag === LATIN_SMALL_LETTER_M) {
-                multiline = true
-            } else if (
-                flag === LATIN_SMALL_LETTER_U &&
-                this.ecmaVersion >= 2015
-            ) {
-                unicode = true
-            } else if (
-                flag === LATIN_SMALL_LETTER_Y &&
-                this.ecmaVersion >= 2015
-            ) {
-                sticky = true
-            } else if (
-                flag === LATIN_SMALL_LETTER_S &&
-                this.ecmaVersion >= 2018
-            ) {
-                dotAll = true
-            } else if (
-                flag === LATIN_SMALL_LETTER_D &&
-                this.ecmaVersion >= 2022
-            ) {
-                hasIndices = true
-            } else if (
-                flag === LATIN_SMALL_LETTER_V &&
-                this.ecmaVersion >= 2024
-            ) {
-                unicodeSets = true
-            } else {
-                this.raise(`Invalid flag '${source[i]}'`, { index: start })
-            }
-        }
-        this.onRegExpFlags(start, end, {
-            global,
-            ignoreCase,
-            multiline,
-            unicode,
-            sticky,
-            dotAll,
-            hasIndices,
-            unicodeSets,
-        })
+        const flags = this.parseFlags(source, start, end)
+        this.onRegExpFlags(start, end, flags)
     }
 
     private _parseFlagsOptionToMode(
@@ -1006,6 +1030,38 @@ export class RegExpValidator {
         }
     }
 
+    private onModifiersEnter(start: number): void {
+        if (this._options.onModifiersEnter) {
+            this._options.onModifiersEnter(start)
+        }
+    }
+
+    private onModifiersLeave(start: number, end: number): void {
+        if (this._options.onModifiersLeave) {
+            this._options.onModifiersLeave(start, end)
+        }
+    }
+
+    private onAddModifiers(
+        start: number,
+        end: number,
+        flags: { ignoreCase: boolean; multiline: boolean; dotAll: boolean },
+    ): void {
+        if (this._options.onAddModifiers) {
+            this._options.onAddModifiers(start, end, flags)
+        }
+    }
+
+    private onRemoveModifiers(
+        start: number,
+        end: number,
+        flags: { ignoreCase: boolean; multiline: boolean; dotAll: boolean },
+    ): void {
+        if (this._options.onRemoveModifiers) {
+            this._options.onRemoveModifiers(start, end, flags)
+        }
+    }
+
     private onCapturingGroupEnter(start: number, name: string | null): void {
         if (this._options.onCapturingGroupEnter) {
             this._options.onCapturingGroupEnter(start, name)
@@ -1625,7 +1681,8 @@ export class RegExpValidator {
      *      `\\` AtomEscape[?UnicodeMode, ?UnicodeSetsMode, ?N]
      *      CharacterClass[?UnicodeMode, ?UnicodeSetsMode]
      *      `(` GroupSpecifier[?UnicodeMode] Disjunction[?UnicodeMode, ?UnicodeSetsMode, ?N] `)`
-     *      `(?:` Disjunction[?UnicodeMode, ?UnicodeSetsMode, ?N] `)`
+     *      `(?` RegularExpressionFlags `:` Disjunction[?UnicodeMode, ?UnicodeSetsMode, ?N] `)`
+     *      `(?` RegularExpressionFlags `-` RegularExpressionFlags `:` Disjunction[?UnicodeMode, ?UnicodeSetsMode, ?N] `)`
      * ```
      * @returns `true` if it consumed the next characters successfully.
      */
@@ -1635,8 +1692,8 @@ export class RegExpValidator {
             this.consumeDot() ||
             this.consumeReverseSolidusAtomEscape() ||
             Boolean(this.consumeCharacterClass()) ||
-            this.consumeUncapturingGroup() ||
-            this.consumeCapturingGroup()
+            this.consumeCapturingGroup() ||
+            this.consumeUncapturingGroup()
         )
     }
 
@@ -1676,14 +1733,26 @@ export class RegExpValidator {
     /**
      * Validate the next characters as the following alternatives if possible.
      * ```
-     *      `(?:` Disjunction[?UnicodeMode, ?UnicodeSetsMode, ?N] )
+     *      `(?` RegularExpressionFlags `:` Disjunction[?UnicodeMode, ?UnicodeSetsMode, ?N] `)`
+     *      `(?` RegularExpressionFlags `-` RegularExpressionFlags `:` Disjunction[?UnicodeMode, ?UnicodeSetsMode, ?N] `)`
+     * RegularExpressionFlags ::
+     *      [empty]
+     *      RegularExpressionFlags IdentifierPartChar
      * ```
      * @returns `true` if it consumed the next characters successfully.
      */
     private consumeUncapturingGroup(): boolean {
         const start = this.index
-        if (this.eat3(LEFT_PARENTHESIS, QUESTION_MARK, COLON)) {
+        if (this.eat2(LEFT_PARENTHESIS, QUESTION_MARK)) {
             this.onGroupEnter(start)
+            if (this.ecmaVersion >= 2025) {
+                this.consumeModifiers()
+            }
+
+            if (!this.eat(COLON)) {
+                this.rewind(start + 1) // Throw an error at the question mark position.
+                this.raise("Invalid group")
+            }
             this.consumeDisjunction()
             if (!this.eat(RIGHT_PARENTHESIS)) {
                 this.raise("Unterminated group")
@@ -1694,6 +1763,53 @@ export class RegExpValidator {
         return false
     }
 
+    /**
+     * Validate the next characters as the following alternatives if possible.
+     * ```
+     *      RegularExpressionFlags
+     *      RegularExpressionFlags `-` RegularExpressionFlags
+     * ```
+     */
+    private consumeModifiers(): boolean {
+        const start = this.index
+        const hasAddModifiers = this.eatModifiers()
+        const addModifiersEnd = this.index
+        const hasHyphen = this.eat(HYPHEN_MINUS)
+        if (!hasAddModifiers && !hasHyphen) {
+            return false
+        }
+        this.onModifiersEnter(start)
+        const addModifiers = this.parseModifiers(start, addModifiersEnd)
+        this.onAddModifiers(start, addModifiersEnd, addModifiers)
+
+        if (hasHyphen) {
+            const modifiersStart = this.index
+            if (
+                !this.eatModifiers() &&
+                !hasAddModifiers &&
+                this.currentCodePoint === COLON
+            ) {
+                this.raise("Invalid empty flags")
+            }
+            const modifiers = this.parseModifiers(modifiersStart, this.index)
+            for (const [flagName] of Object.entries(modifiers).filter(
+                ([, enable]) => enable,
+            ) as [keyof typeof modifiers, boolean][]) {
+                if (addModifiers[flagName]) {
+                    this.raise(
+                        `Duplicated flag '${String.fromCodePoint(
+                            FLAG_PROP_TO_CODEPOINT[flagName],
+                        )}'`,
+                    )
+                }
+            }
+            this.onRemoveModifiers(modifiersStart, this.index, modifiers)
+        }
+
+        this.onModifiersLeave(start, this.index)
+        return true
+    }
+
     /**
      * Validate the next characters as the following alternatives if possible.
      * ```
@@ -1708,9 +1824,15 @@ export class RegExpValidator {
             if (this.ecmaVersion >= 2018) {
                 if (this.consumeGroupSpecifier()) {
                     name = this._lastStrValue
+                } else if (this.currentCodePoint === QUESTION_MARK) {
+                    // Maybe Group with modifiers
+                    this.rewind(start)
+                    return false
                 }
             } else if (this.currentCodePoint === QUESTION_MARK) {
-                this.raise("Invalid group")
+                // Maybe Group with modifiers
+                this.rewind(start)
+                return false
             }
 
             this.onCapturingGroupEnter(start, name)
@@ -1734,8 +1856,9 @@ export class RegExpValidator {
      *      `\` AtomEscape[~U, ?N]
      *      `\` [lookahead = c]
      *      CharacterClass[~U]
-     *      `(?:` Disjunction[~U, ?N] `)`
      *      `(` Disjunction[~U, ?N] `)`
+     *      `(?` RegularExpressionFlags `:` Disjunction[?U, ?N] `)`
+     *      `(?` RegularExpressionFlags `-` RegularExpressionFlags `:` Disjunction[?U, ?N] `)`
      *      InvalidBracedQuantifier
      *      ExtendedPatternCharacter
      * ```
@@ -1747,8 +1870,8 @@ export class RegExpValidator {
             this.consumeReverseSolidusAtomEscape() ||
             this.consumeReverseSolidusFollowedByC() ||
             Boolean(this.consumeCharacterClass()) ||
-            this.consumeUncapturingGroup() ||
             this.consumeCapturingGroup() ||
+            this.consumeUncapturingGroup() ||
             this.consumeInvalidBracedQuantifier() ||
             this.consumeExtendedPatternCharacter()
         )
@@ -1857,6 +1980,7 @@ export class RegExpValidator {
      * @returns `true` if the group name existed.
      */
     private consumeGroupSpecifier(): boolean {
+        const start = this.index
         if (this.eat(QUESTION_MARK)) {
             if (this.eatGroupName()) {
                 if (!this._groupSpecifiers.hasInScope(this._lastStrValue)) {
@@ -1865,7 +1989,8 @@ export class RegExpValidator {
                 }
                 this.raise("Duplicate capture group name")
             }
-            this.raise("Invalid group")
+            // Maybe Group with modifiers
+            this.rewind(start)
         }
         return false
     }
@@ -3380,4 +3505,93 @@ export class RegExpValidator {
         }
         return true
     }
+
+    /**
+     * Eat the next characters as the following alternatives.
+     * ```
+     * RegularExpressionFlags ::
+     *      [empty]
+     *      RegularExpressionFlags RegularExpressionModifier
+     * ```
+     * @returns `true` if it ate the next characters successfully.
+     */
+    private eatModifiers(): boolean {
+        let ate = false
+        while (isRegularExpressionModifier(this.currentCodePoint)) {
+            this.advance()
+            ate = true
+        }
+        return ate
+    }
+
+    /**
+     * Parse a regexp modifiers. E.g. "ims"
+     * @param start The start index in the source code.
+     * @param end The end index in the source code.
+     */
+    private parseModifiers(start: number, end: number) {
+        const { ignoreCase, multiline, dotAll } = this.parseFlags(
+            this._reader.source,
+            start,
+            end,
+        )
+
+        return { ignoreCase, multiline, dotAll }
+    }
+
+    /**
+     * Parse a regexp flags. E.g. "ims"
+     * @param start The start index in the source code.
+     * @param end The end index in the source code.
+     */
+    private parseFlags(
+        source: string,
+        start: number,
+        end: number,
+    ): FlagsRecord {
+        const flags = {
+            global: false,
+            ignoreCase: false,
+            multiline: false,
+            unicode: false,
+            sticky: false,
+            dotAll: false,
+            hasIndices: false,
+            unicodeSets: false,
+        }
+
+        const validFlags = new Set<FlagCodePoint>()
+        validFlags.add(LATIN_SMALL_LETTER_G)
+        validFlags.add(LATIN_SMALL_LETTER_I)
+        validFlags.add(LATIN_SMALL_LETTER_M)
+        if (this.ecmaVersion >= 2015) {
+            validFlags.add(LATIN_SMALL_LETTER_U)
+            validFlags.add(LATIN_SMALL_LETTER_Y)
+            if (this.ecmaVersion >= 2018) {
+                validFlags.add(LATIN_SMALL_LETTER_S)
+                if (this.ecmaVersion >= 2021) {
+                    validFlags.add(LATIN_SMALL_LETTER_D)
+                    if (this.ecmaVersion >= 2024) {
+                        validFlags.add(LATIN_SMALL_LETTER_V)
+                    }
+                }
+            }
+        }
+
+        for (let i = start; i < end; ++i) {
+            const flag = source.charCodeAt(i) as FlagCodePoint
+            if (validFlags.has(flag)) {
+                const prop = FLAG_CODEPOINT_TO_PROP[flag]
+                if (flags[prop]) {
+                    this.raise(`Duplicated flag '${source[i]}'`, {
+                        index: start,
+                    })
+                }
+                flags[prop] = true
+            } else {
+                this.raise(`Invalid flag '${source[i]}'`, { index: start })
+            }
+        }
+        return flags
+    }
 }
diff --git a/src/visitor.ts b/src/visitor.ts
index f7f8c72..a2cb2a0 100644
--- a/src/visitor.ts
+++ b/src/visitor.ts
@@ -13,6 +13,8 @@ import type {
     ExpressionCharacterClass,
     Flags,
     Group,
+    ModifierFlags,
+    Modifiers,
     Node,
     Pattern,
     Quantifier,
@@ -83,6 +85,12 @@ export class RegExpVisitor {
             case "Group":
                 this.visitGroup(node)
                 break
+            case "Modifiers":
+                this.visitModifiers(node)
+                break
+            case "ModifierFlags":
+                this.visitModifierFlags(node)
+                break
             case "Pattern":
                 this.visitPattern(node)
                 break
@@ -239,12 +247,39 @@ export class RegExpVisitor {
         if (this._handlers.onGroupEnter) {
             this._handlers.onGroupEnter(node)
         }
+        if (node.modifiers) {
+            this.visit(node.modifiers)
+        }
         node.alternatives.forEach(this.visit, this)
         if (this._handlers.onGroupLeave) {
             this._handlers.onGroupLeave(node)
         }
     }
 
+    private visitModifiers(node: Modifiers): void {
+        if (this._handlers.onModifiersEnter) {
+            this._handlers.onModifiersEnter(node)
+        }
+        if (node.add) {
+            this.visit(node.add)
+        }
+        if (node.remove) {
+            this.visit(node.remove)
+        }
+        if (this._handlers.onModifiersLeave) {
+            this._handlers.onModifiersLeave(node)
+        }
+    }
+
+    private visitModifierFlags(node: ModifierFlags): void {
+        if (this._handlers.onModifierFlagsEnter) {
+            this._handlers.onModifierFlagsEnter(node)
+        }
+        if (this._handlers.onModifierFlagsLeave) {
+            this._handlers.onModifierFlagsLeave(node)
+        }
+    }
+
     private visitPattern(node: Pattern): void {
         if (this._handlers.onPatternEnter) {
             this._handlers.onPatternEnter(node)
@@ -321,6 +356,10 @@ export namespace RegExpVisitor {
         onFlagsLeave?: (node: Flags) => void
         onGroupEnter?: (node: Group) => void
         onGroupLeave?: (node: Group) => void
+        onModifierFlagsEnter?: (node: ModifierFlags) => void
+        onModifierFlagsLeave?: (node: ModifierFlags) => void
+        onModifiersEnter?: (node: Modifiers) => void
+        onModifiersLeave?: (node: Modifiers) => void
         onPatternEnter?: (node: Pattern) => void
         onPatternLeave?: (node: Pattern) => void
         onQuantifierEnter?: (node: Quantifier) => void
diff --git a/test/fixtures/parser/literal/basic-valid-2015-u.json b/test/fixtures/parser/literal/basic-valid-2015-u.json
index 963494d..7e510e2 100644
--- a/test/fixtures/parser/literal/basic-valid-2015-u.json
+++ b/test/fixtures/parser/literal/basic-valid-2015-u.json
@@ -2519,6 +2519,7 @@
                   "start": 1,
                   "end": 6,
                   "raw": "(?:a)",
+                  "modifiers": null,
                   "alternatives": [
                     {
                       "type": "Alternative",
@@ -11277,6 +11278,7 @@
                     "start": 48,
                     "end": 67,
                     "raw": "(?:\\.[a-zA-Z0-9-]+)",
+                    "modifiers": null,
                     "alternatives": [
                       {
                         "type": "Alternative",
diff --git a/test/fixtures/parser/literal/basic-valid-2015.json b/test/fixtures/parser/literal/basic-valid-2015.json
index ed988e9..36f3603 100644
--- a/test/fixtures/parser/literal/basic-valid-2015.json
+++ b/test/fixtures/parser/literal/basic-valid-2015.json
@@ -3933,6 +3933,7 @@
                   "start": 1,
                   "end": 6,
                   "raw": "(?:a)",
+                  "modifiers": null,
                   "alternatives": [
                     {
                       "type": "Alternative",
@@ -4087,6 +4088,7 @@
                   "start": 1,
                   "end": 6,
                   "raw": "(?:a)",
+                  "modifiers": null,
                   "alternatives": [
                     {
                       "type": "Alternative",
@@ -5189,6 +5191,7 @@
                   "start": 1,
                   "end": 6,
                   "raw": "(?:a)",
+                  "modifiers": null,
                   "alternatives": [
                     {
                       "type": "Alternative",
@@ -17010,6 +17013,7 @@
                     "start": 48,
                     "end": 67,
                     "raw": "(?:\\.[a-zA-Z0-9-]+)",
+                    "modifiers": null,
                     "alternatives": [
                       {
                         "type": "Alternative",
diff --git a/test/fixtures/parser/literal/basic-valid.json b/test/fixtures/parser/literal/basic-valid.json
index e8b04da..80189ea 100644
--- a/test/fixtures/parser/literal/basic-valid.json
+++ b/test/fixtures/parser/literal/basic-valid.json
@@ -3933,6 +3933,7 @@
                   "start": 1,
                   "end": 6,
                   "raw": "(?:a)",
+                  "modifiers": null,
                   "alternatives": [
                     {
                       "type": "Alternative",
@@ -4087,6 +4088,7 @@
                   "start": 1,
                   "end": 6,
                   "raw": "(?:a)",
+                  "modifiers": null,
                   "alternatives": [
                     {
                       "type": "Alternative",
@@ -5189,6 +5191,7 @@
                   "start": 1,
                   "end": 6,
                   "raw": "(?:a)",
+                  "modifiers": null,
                   "alternatives": [
                     {
                       "type": "Alternative",
@@ -17010,6 +17013,7 @@
                     "start": 48,
                     "end": 67,
                     "raw": "(?:\\.[a-zA-Z0-9-]+)",
+                    "modifiers": null,
                     "alternatives": [
                       {
                         "type": "Alternative",
diff --git a/test/fixtures/parser/literal/duplicate-named-capturing-group-valid-2025.json b/test/fixtures/parser/literal/duplicate-named-capturing-group-valid-2025.json
index de6bca9..56ada83 100644
--- a/test/fixtures/parser/literal/duplicate-named-capturing-group-valid-2025.json
+++ b/test/fixtures/parser/literal/duplicate-named-capturing-group-valid-2025.json
@@ -314,6 +314,7 @@
                   "start": 1,
                   "end": 39,
                   "raw": "(?:(?:(?<x>a)\\k<x>|(?<x>b)\\k<x>)|(?:))",
+                  "modifiers": null,
                   "alternatives": [
                     {
                       "type": "Alternative",
@@ -328,6 +329,7 @@
                           "start": 4,
                           "end": 33,
                           "raw": "(?:(?<x>a)\\k<x>|(?<x>b)\\k<x>)",
+                          "modifiers": null,
                           "alternatives": [
                             {
                               "type": "Alternative",
@@ -454,6 +456,7 @@
                           "start": 34,
                           "end": 38,
                           "raw": "(?:)",
+                          "modifiers": null,
                           "alternatives": [
                             {
                               "type": "Alternative",
@@ -530,6 +533,7 @@
                   "start": 1,
                   "end": 39,
                   "raw": "(?:(?:(?<x>a\\k<x>)|(?<x>b\\k<x>))|(?:))",
+                  "modifiers": null,
                   "alternatives": [
                     {
                       "type": "Alternative",
@@ -544,6 +548,7 @@
                           "start": 4,
                           "end": 33,
                           "raw": "(?:(?<x>a\\k<x>)|(?<x>b\\k<x>))",
+                          "modifiers": null,
                           "alternatives": [
                             {
                               "type": "Alternative",
@@ -670,6 +675,7 @@
                           "start": 34,
                           "end": 38,
                           "raw": "(?:)",
+                          "modifiers": null,
                           "alternatives": [
                             {
                               "type": "Alternative",
diff --git a/test/fixtures/parser/literal/flags.json b/test/fixtures/parser/literal/flags.json
index ec87673..52c2834 100644
--- a/test/fixtures/parser/literal/flags.json
+++ b/test/fixtures/parser/literal/flags.json
@@ -31,6 +31,7 @@
                   "start": 1,
                   "end": 5,
                   "raw": "(?:)",
+                  "modifiers": null,
                   "alternatives": [
                     {
                       "type": "Alternative",
@@ -90,6 +91,7 @@
                   "start": 1,
                   "end": 5,
                   "raw": "(?:)",
+                  "modifiers": null,
                   "alternatives": [
                     {
                       "type": "Alternative",
@@ -149,6 +151,7 @@
                   "start": 1,
                   "end": 5,
                   "raw": "(?:)",
+                  "modifiers": null,
                   "alternatives": [
                     {
                       "type": "Alternative",
@@ -208,6 +211,7 @@
                   "start": 1,
                   "end": 5,
                   "raw": "(?:)",
+                  "modifiers": null,
                   "alternatives": [
                     {
                       "type": "Alternative",
@@ -267,6 +271,7 @@
                   "start": 1,
                   "end": 5,
                   "raw": "(?:)",
+                  "modifiers": null,
                   "alternatives": [
                     {
                       "type": "Alternative",
@@ -326,6 +331,7 @@
                   "start": 1,
                   "end": 5,
                   "raw": "(?:)",
+                  "modifiers": null,
                   "alternatives": [
                     {
                       "type": "Alternative",
diff --git a/test/fixtures/parser/literal/modifiers-invalid-2024.json b/test/fixtures/parser/literal/modifiers-invalid-2024.json
new file mode 100644
index 0000000..762b609
--- /dev/null
+++ b/test/fixtures/parser/literal/modifiers-invalid-2024.json
@@ -0,0 +1,26 @@
+{
+  "options": {
+    "strict": false,
+    "ecmaVersion": 2024
+  },
+  "patterns": {
+    "/(?ims-ims:sub_expression)/": {
+      "error": {
+        "message": "Invalid regular expression: /(?ims-ims:sub_expression)/: Invalid group",
+        "index": 2
+      }
+    },
+    "/(?ims:sub_expression)/": {
+      "error": {
+        "message": "Invalid regular expression: /(?ims:sub_expression)/: Invalid group",
+        "index": 2
+      }
+    },
+    "/(?-ims:sub_expression)/": {
+      "error": {
+        "message": "Invalid regular expression: /(?-ims:sub_expression)/: Invalid group",
+        "index": 2
+      }
+    }
+  }
+}
\ No newline at end of file
diff --git a/test/fixtures/parser/literal/modifiers-invalid-2025.json b/test/fixtures/parser/literal/modifiers-invalid-2025.json
new file mode 100644
index 0000000..946ef80
--- /dev/null
+++ b/test/fixtures/parser/literal/modifiers-invalid-2025.json
@@ -0,0 +1,56 @@
+{
+  "options": {
+    "strict": false,
+    "ecmaVersion": 2025
+  },
+  "patterns": {
+    "/(?-:sub_expression)?/": {
+      "error": {
+        "message": "Invalid regular expression: /(?-:sub_expression)?/: Invalid empty flags",
+        "index": 4
+      }
+    },
+    "/(?unknown:sub_expression)?/": {
+      "error": {
+        "message": "Invalid regular expression: /(?unknown:sub_expression)?/: Invalid group",
+        "index": 2
+      }
+    },
+    "/(?i-unknown:sub_expression)?/": {
+      "error": {
+        "message": "Invalid regular expression: /(?i-unknown:sub_expression)?/: Invalid group",
+        "index": 2
+      }
+    },
+    "/(?ii:sub_expression)?/": {
+      "error": {
+        "message": "Invalid regular expression: /(?ii:sub_expression)?/: Duplicated flag 'i'",
+        "index": 3
+      }
+    },
+    "/(?-ii:sub_expression)?/": {
+      "error": {
+        "message": "Invalid regular expression: /(?-ii:sub_expression)?/: Duplicated flag 'i'",
+        "index": 4
+      }
+    },
+    "/(?i-i:sub_expression)?/": {
+      "error": {
+        "message": "Invalid regular expression: /(?i-i:sub_expression)?/: Duplicated flag 'i'",
+        "index": 6
+      }
+    },
+    "/(?iu:sub_expression)?/": {
+      "error": {
+        "message": "Invalid regular expression: /(?iu:sub_expression)?/: Invalid group",
+        "index": 2
+      }
+    },
+    "/(?-iu:sub_expression)?/": {
+      "error": {
+        "message": "Invalid regular expression: /(?-iu:sub_expression)?/: Invalid group",
+        "index": 2
+      }
+    }
+  }
+}
\ No newline at end of file
diff --git a/test/fixtures/parser/literal/modifiers-valid-2025.json b/test/fixtures/parser/literal/modifiers-valid-2025.json
new file mode 100644
index 0000000..ef709c0
--- /dev/null
+++ b/test/fixtures/parser/literal/modifiers-valid-2025.json
@@ -0,0 +1,461 @@
+{
+  "options": {
+    "strict": false,
+    "ecmaVersion": 2025
+  },
+  "patterns": {
+    "/(?i-m:p)/": {
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?i-m:p)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?i-m:p)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?i-m:p)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?i-m:p)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "i-m",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 6,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 8,
+                      "raw": "p",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "p",
+                          "value": 112
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
+      }
+    },
+    "/(?ims:p)/u": {
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 11,
+        "raw": "/(?ims:p)/u",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?ims:p)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?ims:p)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?ims:p)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "ims",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 6,
+                      "raw": "ims",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": true
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 8,
+                      "raw": "p",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "p",
+                          "value": 112
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 11,
+          "raw": "u",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": true,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
+      }
+    },
+    "/(?-ims:p)?/": {
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 12,
+        "raw": "/(?-ims:p)?/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 11,
+          "raw": "(?-ims:p)?",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 11,
+              "raw": "(?-ims:p)?",
+              "elements": [
+                {
+                  "type": "Quantifier",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 11,
+                  "raw": "(?-ims:p)?",
+                  "min": 0,
+                  "max": 1,
+                  "greedy": true,
+                  "element": {
+                    "type": "Group",
+                    "parent": "♻️..",
+                    "start": 1,
+                    "end": 10,
+                    "raw": "(?-ims:p)",
+                    "modifiers": {
+                      "type": "Modifiers",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 7,
+                      "raw": "-ims",
+                      "add": {
+                        "type": "ModifierFlags",
+                        "parent": "♻️..",
+                        "start": 3,
+                        "end": 3,
+                        "raw": "",
+                        "ignoreCase": false,
+                        "multiline": false,
+                        "dotAll": false
+                      },
+                      "remove": {
+                        "type": "ModifierFlags",
+                        "parent": "♻️..",
+                        "start": 4,
+                        "end": 7,
+                        "raw": "ims",
+                        "ignoreCase": true,
+                        "multiline": true,
+                        "dotAll": true
+                      }
+                    },
+                    "alternatives": [
+                      {
+                        "type": "Alternative",
+                        "parent": "♻️../..",
+                        "start": 8,
+                        "end": 9,
+                        "raw": "p",
+                        "elements": [
+                          {
+                            "type": "Character",
+                            "parent": "♻️../..",
+                            "start": 8,
+                            "end": 9,
+                            "raw": "p",
+                            "value": 112
+                          }
+                        ]
+                      }
+                    ]
+                  }
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 12,
+          "end": 12,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
+      }
+    },
+    "/(?:no-modifiers)?/": {
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 19,
+        "raw": "/(?:no-modifiers)?/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 18,
+          "raw": "(?:no-modifiers)?",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 18,
+              "raw": "(?:no-modifiers)?",
+              "elements": [
+                {
+                  "type": "Quantifier",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 18,
+                  "raw": "(?:no-modifiers)?",
+                  "min": 0,
+                  "max": 1,
+                  "greedy": true,
+                  "element": {
+                    "type": "Group",
+                    "parent": "♻️..",
+                    "start": 1,
+                    "end": 17,
+                    "raw": "(?:no-modifiers)",
+                    "modifiers": null,
+                    "alternatives": [
+                      {
+                        "type": "Alternative",
+                        "parent": "♻️../..",
+                        "start": 4,
+                        "end": 16,
+                        "raw": "no-modifiers",
+                        "elements": [
+                          {
+                            "type": "Character",
+                            "parent": "♻️../..",
+                            "start": 4,
+                            "end": 5,
+                            "raw": "n",
+                            "value": 110
+                          },
+                          {
+                            "type": "Character",
+                            "parent": "♻️../..",
+                            "start": 5,
+                            "end": 6,
+                            "raw": "o",
+                            "value": 111
+                          },
+                          {
+                            "type": "Character",
+                            "parent": "♻️../..",
+                            "start": 6,
+                            "end": 7,
+                            "raw": "-",
+                            "value": 45
+                          },
+                          {
+                            "type": "Character",
+                            "parent": "♻️../..",
+                            "start": 7,
+                            "end": 8,
+                            "raw": "m",
+                            "value": 109
+                          },
+                          {
+                            "type": "Character",
+                            "parent": "♻️../..",
+                            "start": 8,
+                            "end": 9,
+                            "raw": "o",
+                            "value": 111
+                          },
+                          {
+                            "type": "Character",
+                            "parent": "♻️../..",
+                            "start": 9,
+                            "end": 10,
+                            "raw": "d",
+                            "value": 100
+                          },
+                          {
+                            "type": "Character",
+                            "parent": "♻️../..",
+                            "start": 10,
+                            "end": 11,
+                            "raw": "i",
+                            "value": 105
+                          },
+                          {
+                            "type": "Character",
+                            "parent": "♻️../..",
+                            "start": 11,
+                            "end": 12,
+                            "raw": "f",
+                            "value": 102
+                          },
+                          {
+                            "type": "Character",
+                            "parent": "♻️../..",
+                            "start": 12,
+                            "end": 13,
+                            "raw": "i",
+                            "value": 105
+                          },
+                          {
+                            "type": "Character",
+                            "parent": "♻️../..",
+                            "start": 13,
+                            "end": 14,
+                            "raw": "e",
+                            "value": 101
+                          },
+                          {
+                            "type": "Character",
+                            "parent": "♻️../..",
+                            "start": 14,
+                            "end": 15,
+                            "raw": "r",
+                            "value": 114
+                          },
+                          {
+                            "type": "Character",
+                            "parent": "♻️../..",
+                            "start": 15,
+                            "end": 16,
+                            "raw": "s",
+                            "value": 115
+                          }
+                        ]
+                      }
+                    ]
+                  }
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 19,
+          "end": 19,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
+      }
+    }
+  }
+}
\ No newline at end of file
diff --git a/test/fixtures/parser/literal/named-capturing-group-invalid-2018.json b/test/fixtures/parser/literal/named-capturing-group-invalid-2018.json
index ed4d33d..f4ad8a7 100644
--- a/test/fixtures/parser/literal/named-capturing-group-invalid-2018.json
+++ b/test/fixtures/parser/literal/named-capturing-group-invalid-2018.json
@@ -7,13 +7,13 @@
     "/(?a/": {
       "error": {
         "message": "Invalid regular expression: /(?a/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?a)/": {
       "error": {
         "message": "Invalid regular expression: /(?a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?</": {
diff --git a/test/fixtures/parser/literal/named-capturing-group-valid-2018.json b/test/fixtures/parser/literal/named-capturing-group-valid-2018.json
index 169b435..12b1e31 100644
--- a/test/fixtures/parser/literal/named-capturing-group-valid-2018.json
+++ b/test/fixtures/parser/literal/named-capturing-group-valid-2018.json
@@ -101,6 +101,7 @@
                   "start": 1,
                   "end": 6,
                   "raw": "(?:a)",
+                  "modifiers": null,
                   "alternatives": [
                     {
                       "type": "Alternative",
diff --git a/test/fixtures/parser/literal/test262/Symbol.matchAll-and-regexp-unicode-property-escapes-and-regexp-v-flag.json b/test/fixtures/parser/literal/test262/Symbol.matchAll-and-regexp-unicode-property-escapes-and-regexp-v-flag.json
index fe17563..5aa6e7b 100644
--- a/test/fixtures/parser/literal/test262/Symbol.matchAll-and-regexp-unicode-property-escapes-and-regexp-v-flag.json
+++ b/test/fixtures/parser/literal/test262/Symbol.matchAll-and-regexp-unicode-property-escapes-and-regexp-v-flag.json
@@ -31,6 +31,7 @@
                   "start": 1,
                   "end": 5,
                   "raw": "(?:)",
+                  "modifiers": null,
                   "alternatives": [
                     {
                       "type": "Alternative",
diff --git a/test/fixtures/parser/literal/test262/Symbol.matchAll-and-regexp-v-flag.json b/test/fixtures/parser/literal/test262/Symbol.matchAll-and-regexp-v-flag.json
index cdf7a8a..61060d5 100644
--- a/test/fixtures/parser/literal/test262/Symbol.matchAll-and-regexp-v-flag.json
+++ b/test/fixtures/parser/literal/test262/Symbol.matchAll-and-regexp-v-flag.json
@@ -31,6 +31,7 @@
                   "start": 1,
                   "end": 5,
                   "raw": "(?:)",
+                  "modifiers": null,
                   "alternatives": [
                     {
                       "type": "Alternative",
diff --git a/test/fixtures/parser/literal/test262/not-categorized.json b/test/fixtures/parser/literal/test262/not-categorized.json
index 75600ff..dc72c2b 100644
--- a/test/fixtures/parser/literal/test262/not-categorized.json
+++ b/test/fixtures/parser/literal/test262/not-categorized.json
@@ -3540,6 +3540,7 @@
                     "start": 1,
                     "end": 10,
                     "raw": "(?:ab|cd)",
+                    "modifiers": null,
                     "alternatives": [
                       {
                         "type": "Alternative",
@@ -3667,6 +3668,7 @@
                   "start": 1,
                   "end": 10,
                   "raw": "(?:ab|cd)",
+                  "modifiers": null,
                   "alternatives": [
                     {
                       "type": "Alternative",
diff --git a/test/fixtures/parser/literal/test262/regexp-dotall.json b/test/fixtures/parser/literal/test262/regexp-dotall.json
index ace8b20..7abea02 100644
--- a/test/fixtures/parser/literal/test262/regexp-dotall.json
+++ b/test/fixtures/parser/literal/test262/regexp-dotall.json
@@ -32,6 +32,7 @@
                   "start": 1,
                   "end": 5,
                   "raw": "(?:)",
+                  "modifiers": null,
                   "alternatives": [
                     {
                       "type": "Alternative",
diff --git a/test/fixtures/parser/literal/test262/regexp-duplicate-named-groups-and-regexp-match-indices.json b/test/fixtures/parser/literal/test262/regexp-duplicate-named-groups-and-regexp-match-indices.json
index 44383fd..beda2fd 100644
--- a/test/fixtures/parser/literal/test262/regexp-duplicate-named-groups-and-regexp-match-indices.json
+++ b/test/fixtures/parser/literal/test262/regexp-duplicate-named-groups-and-regexp-match-indices.json
@@ -41,6 +41,7 @@
                     "start": 1,
                     "end": 31,
                     "raw": "(?:(?:(?<x>a)|(?<x>b)|c)\\k<x>)",
+                    "modifiers": null,
                     "alternatives": [
                       {
                         "type": "Alternative",
@@ -55,6 +56,7 @@
                             "start": 4,
                             "end": 25,
                             "raw": "(?:(?<x>a)|(?<x>b)|c)",
+                            "modifiers": null,
                             "alternatives": [
                               {
                                 "type": "Alternative",
@@ -219,6 +221,7 @@
                   "start": 1,
                   "end": 27,
                   "raw": "(?:(?<x>a)|(?<y>a)(?<x>b))",
+                  "modifiers": null,
                   "alternatives": [
                     {
                       "type": "Alternative",
@@ -330,6 +333,7 @@
                   "start": 27,
                   "end": 46,
                   "raw": "(?:(?<z>c)|(?<z>d))",
+                  "modifiers": null,
                   "alternatives": [
                     {
                       "type": "Alternative",
diff --git a/test/fixtures/parser/literal/test262/regexp-duplicate-named-groups.json b/test/fixtures/parser/literal/test262/regexp-duplicate-named-groups.json
index 1bafeb6..0b608a4 100644
--- a/test/fixtures/parser/literal/test262/regexp-duplicate-named-groups.json
+++ b/test/fixtures/parser/literal/test262/regexp-duplicate-named-groups.json
@@ -44,6 +44,7 @@
                     "start": 1,
                     "end": 29,
                     "raw": "(?:(?:(?<x>a)|(?<x>b))\\k<x>)",
+                    "modifiers": null,
                     "alternatives": [
                       {
                         "type": "Alternative",
@@ -58,6 +59,7 @@
                             "start": 4,
                             "end": 23,
                             "raw": "(?:(?<x>a)|(?<x>b))",
+                            "modifiers": null,
                             "alternatives": [
                               {
                                 "type": "Alternative",
@@ -214,6 +216,7 @@
                     "start": 1,
                     "end": 31,
                     "raw": "(?:(?:(?<x>a)|(?<x>b)|c)\\k<x>)",
+                    "modifiers": null,
                     "alternatives": [
                       {
                         "type": "Alternative",
@@ -228,6 +231,7 @@
                             "start": 4,
                             "end": 25,
                             "raw": "(?:(?<x>a)|(?<x>b)|c)",
+                            "modifiers": null,
                             "alternatives": [
                               {
                                 "type": "Alternative",
@@ -392,6 +396,7 @@
                   "start": 1,
                   "end": 20,
                   "raw": "(?:(?<x>a)|(?<x>b))",
+                  "modifiers": null,
                   "alternatives": [
                     {
                       "type": "Alternative",
@@ -534,6 +539,7 @@
                   "start": 1,
                   "end": 27,
                   "raw": "(?:(?<x>a)|(?<y>a)(?<x>b))",
+                  "modifiers": null,
                   "alternatives": [
                     {
                       "type": "Alternative",
@@ -645,6 +651,7 @@
                   "start": 27,
                   "end": 46,
                   "raw": "(?:(?<z>c)|(?<z>d))",
+                  "modifiers": null,
                   "alternatives": [
                     {
                       "type": "Alternative",
@@ -809,6 +816,7 @@
                   "start": 9,
                   "end": 20,
                   "raw": "(?:zy\\k<a>)",
+                  "modifiers": null,
                   "alternatives": [
                     {
                       "type": "Alternative",
@@ -1563,6 +1571,7 @@
                   "start": 2,
                   "end": 23,
                   "raw": "(?:(?<a>x)|(?<a>y)|z)",
+                  "modifiers": null,
                   "alternatives": [
                     {
                       "type": "Alternative",
@@ -1747,6 +1756,7 @@
                     "start": 2,
                     "end": 23,
                     "raw": "(?:(?<a>x)|(?<a>y)|z)",
+                    "modifiers": null,
                     "alternatives": [
                       {
                         "type": "Alternative",
diff --git a/test/fixtures/parser/literal/test262/regexp-lookbehind.json b/test/fixtures/parser/literal/test262/regexp-lookbehind.json
index 0cfaf0d..5b40f2d 100644
--- a/test/fixtures/parser/literal/test262/regexp-lookbehind.json
+++ b/test/fixtures/parser/literal/test262/regexp-lookbehind.json
@@ -2844,6 +2844,7 @@
                                     "start": 6,
                                     "end": 16,
                                     "raw": "(?:b\\d{2})",
+                                    "modifiers": null,
                                     "alternatives": [
                                       {
                                         "type": "Alternative",
@@ -3126,6 +3127,7 @@
                           "start": 5,
                           "end": 12,
                           "raw": "(?:\\1b)",
+                          "modifiers": null,
                           "alternatives": [
                             {
                               "type": "Alternative",
@@ -3270,6 +3272,7 @@
                           "start": 5,
                           "end": 13,
                           "raw": "(?:\\1|b)",
+                          "modifiers": null,
                           "alternatives": [
                             {
                               "type": "Alternative",
diff --git a/test/fixtures/parser/literal/test262/regexp-modifiers.json b/test/fixtures/parser/literal/test262/regexp-modifiers.json
index 6b57d82..f5f786e 100644
--- a/test/fixtures/parser/literal/test262/regexp-modifiers.json
+++ b/test/fixtures/parser/literal/test262/regexp-modifiers.json
@@ -141,1585 +141,19156 @@
     "/(?-1:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?-1:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?-:a)/": {
       "error": {
-        "message": "Invalid regular expression: /(?-:a)/: Invalid group",
-        "index": 3
+        "message": "Invalid regular expression: /(?-:a)/: Invalid empty flags",
+        "index": 4
       }
     },
     "/(?-I:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?-I:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?-M:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?-M:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?-Q:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?-Q:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?-S:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?-S:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?-d:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?-d:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?-g:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?-g:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?-i:(?-i:))/": {
-      "error": {
-        "message": "Invalid regular expression: /(?-i:(?-i:))/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 14,
+        "raw": "/(?-i:(?-i:))/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 13,
+          "raw": "(?-i:(?-i:))",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 13,
+              "raw": "(?-i:(?-i:))",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 13,
+                  "raw": "(?-i:(?-i:))",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 12,
+                      "raw": "(?-i:)",
+                      "elements": [
+                        {
+                          "type": "Group",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 12,
+                          "raw": "(?-i:)",
+                          "modifiers": {
+                            "type": "Modifiers",
+                            "parent": "♻️..",
+                            "start": 8,
+                            "end": 10,
+                            "raw": "-i",
+                            "add": {
+                              "type": "ModifierFlags",
+                              "parent": "♻️..",
+                              "start": 8,
+                              "end": 8,
+                              "raw": "",
+                              "ignoreCase": false,
+                              "multiline": false,
+                              "dotAll": false
+                            },
+                            "remove": {
+                              "type": "ModifierFlags",
+                              "parent": "♻️..",
+                              "start": 9,
+                              "end": 10,
+                              "raw": "i",
+                              "ignoreCase": true,
+                              "multiline": false,
+                              "dotAll": false
+                            }
+                          },
+                          "alternatives": [
+                            {
+                              "type": "Alternative",
+                              "parent": "♻️../..",
+                              "start": 11,
+                              "end": 11,
+                              "raw": "",
+                              "elements": []
+                            }
+                          ]
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 14,
+          "end": 14,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-i:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?-i:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 8,
+        "raw": "/(?-i:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 7,
+          "raw": "(?-i:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 7,
+              "raw": "(?-i:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 7,
+                  "raw": "(?-i:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 6,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 8,
+          "end": 8,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-i:)/i": {
-      "error": {
-        "message": "Invalid regular expression: /(?-i:)/i: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?-i:)/i",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 7,
+          "raw": "(?-i:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 7,
+              "raw": "(?-i:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 7,
+                  "raw": "(?-i:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 6,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 8,
+          "end": 9,
+          "raw": "i",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-i:.es)/i": {
-      "error": {
-        "message": "Invalid regular expression: /(?-i:.es)/i: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 12,
+        "raw": "/(?-i:.es)/i",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 10,
+          "raw": "(?-i:.es)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 10,
+              "raw": "(?-i:.es)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 10,
+                  "raw": "(?-i:.es)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 9,
+                      "raw": ".es",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "s",
+                          "value": 115
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 11,
+          "end": 12,
+          "raw": "i",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-i:.es)/is": {
-      "error": {
-        "message": "Invalid regular expression: /(?-i:.es)/is: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 13,
+        "raw": "/(?-i:.es)/is",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 10,
+          "raw": "(?-i:.es)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 10,
+              "raw": "(?-i:.es)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 10,
+                  "raw": "(?-i:.es)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 9,
+                      "raw": ".es",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "s",
+                          "value": 115
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 11,
+          "end": 13,
+          "raw": "is",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": true,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-i:Z\\B)/ui": {
-      "error": {
-        "message": "Invalid regular expression: /(?-i:Z\\B)/ui: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 13,
+        "raw": "/(?-i:Z\\B)/ui",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 10,
+          "raw": "(?-i:Z\\B)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 10,
+              "raw": "(?-i:Z\\B)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 10,
+                  "raw": "(?-i:Z\\B)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 9,
+                      "raw": "Z\\B",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "Z",
+                          "value": 90
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 9,
+                          "raw": "\\B",
+                          "kind": "word",
+                          "negate": true
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 11,
+          "end": 13,
+          "raw": "ui",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": true,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-i:[^ab])c/i": {
-      "error": {
-        "message": "Invalid regular expression: /(?-i:[^ab])c/i: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 15,
+        "raw": "/(?-i:[^ab])c/i",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 13,
+          "raw": "(?-i:[^ab])c",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 13,
+              "raw": "(?-i:[^ab])c",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 12,
+                  "raw": "(?-i:[^ab])",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 11,
+                      "raw": "[^ab]",
+                      "elements": [
+                        {
+                          "type": "CharacterClass",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 11,
+                          "raw": "[^ab]",
+                          "unicodeSets": false,
+                          "negate": true,
+                          "elements": [
+                            {
+                              "type": "Character",
+                              "parent": "♻️../..",
+                              "start": 8,
+                              "end": 9,
+                              "raw": "a",
+                              "value": 97
+                            },
+                            {
+                              "type": "Character",
+                              "parent": "♻️../..",
+                              "start": 9,
+                              "end": 10,
+                              "raw": "b",
+                              "value": 98
+                            }
+                          ]
+                        }
+                      ]
+                    }
+                  ]
+                },
+                {
+                  "type": "Character",
+                  "parent": "♻️../..",
+                  "start": 12,
+                  "end": 13,
+                  "raw": "c",
+                  "value": 99
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 14,
+          "end": 15,
+          "raw": "i",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-i:[ab])c/i": {
-      "error": {
-        "message": "Invalid regular expression: /(?-i:[ab])c/i: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 14,
+        "raw": "/(?-i:[ab])c/i",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 12,
+          "raw": "(?-i:[ab])c",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 12,
+              "raw": "(?-i:[ab])c",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 11,
+                  "raw": "(?-i:[ab])",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 10,
+                      "raw": "[ab]",
+                      "elements": [
+                        {
+                          "type": "CharacterClass",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 10,
+                          "raw": "[ab]",
+                          "unicodeSets": false,
+                          "negate": false,
+                          "elements": [
+                            {
+                              "type": "Character",
+                              "parent": "♻️../..",
+                              "start": 7,
+                              "end": 8,
+                              "raw": "a",
+                              "value": 97
+                            },
+                            {
+                              "type": "Character",
+                              "parent": "♻️../..",
+                              "start": 8,
+                              "end": 9,
+                              "raw": "b",
+                              "value": 98
+                            }
+                          ]
+                        }
+                      ]
+                    }
+                  ]
+                },
+                {
+                  "type": "Character",
+                  "parent": "♻️../..",
+                  "start": 11,
+                  "end": 12,
+                  "raw": "c",
+                  "value": 99
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 13,
+          "end": 14,
+          "raw": "i",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-i:\\P{Lu})/ui": {
-      "error": {
-        "message": "Invalid regular expression: /(?-i:\\P{Lu})/ui: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 16,
+        "raw": "/(?-i:\\P{Lu})/ui",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 13,
+          "raw": "(?-i:\\P{Lu})",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 13,
+              "raw": "(?-i:\\P{Lu})",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 13,
+                  "raw": "(?-i:\\P{Lu})",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 12,
+                      "raw": "\\P{Lu}",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 12,
+                          "raw": "\\P{Lu}",
+                          "kind": "property",
+                          "strings": false,
+                          "key": "General_Category",
+                          "value": "Lu",
+                          "negate": true
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 14,
+          "end": 16,
+          "raw": "ui",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": true,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-i:\\W)/ui": {
-      "error": {
-        "message": "Invalid regular expression: /(?-i:\\W)/ui: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 12,
+        "raw": "/(?-i:\\W)/ui",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?-i:\\W)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?-i:\\W)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?-i:\\W)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 8,
+                      "raw": "\\W",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 8,
+                          "raw": "\\W",
+                          "kind": "word",
+                          "negate": true
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 12,
+          "raw": "ui",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": true,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-i:\\b)/ui": {
-      "error": {
-        "message": "Invalid regular expression: /(?-i:\\b)/ui: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 12,
+        "raw": "/(?-i:\\b)/ui",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?-i:\\b)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?-i:\\b)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?-i:\\b)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 8,
+                      "raw": "\\b",
+                      "elements": [
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 8,
+                          "raw": "\\b",
+                          "kind": "word",
+                          "negate": false
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 12,
+          "raw": "ui",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": true,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-i:\\p{Lu})/ui": {
-      "error": {
-        "message": "Invalid regular expression: /(?-i:\\p{Lu})/ui: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 16,
+        "raw": "/(?-i:\\p{Lu})/ui",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 13,
+          "raw": "(?-i:\\p{Lu})",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 13,
+              "raw": "(?-i:\\p{Lu})",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 13,
+                  "raw": "(?-i:\\p{Lu})",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 12,
+                      "raw": "\\p{Lu}",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 12,
+                          "raw": "\\p{Lu}",
+                          "kind": "property",
+                          "strings": false,
+                          "key": "General_Category",
+                          "value": "Lu",
+                          "negate": false
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 14,
+          "end": 16,
+          "raw": "ui",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": true,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-i:\\u0061)b/i": {
-      "error": {
-        "message": "Invalid regular expression: /(?-i:\\u0061)b/i: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 16,
+        "raw": "/(?-i:\\u0061)b/i",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 14,
+          "raw": "(?-i:\\u0061)b",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 14,
+              "raw": "(?-i:\\u0061)b",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 13,
+                  "raw": "(?-i:\\u0061)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 12,
+                      "raw": "\\u0061",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 12,
+                          "raw": "\\u0061",
+                          "value": 97
+                        }
+                      ]
+                    }
+                  ]
+                },
+                {
+                  "type": "Character",
+                  "parent": "♻️../..",
+                  "start": 13,
+                  "end": 14,
+                  "raw": "b",
+                  "value": 98
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 15,
+          "end": 16,
+          "raw": "i",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-i:\\u{0061})b/iu": {
-      "error": {
-        "message": "Invalid regular expression: /(?-i:\\u{0061})b/iu: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 19,
+        "raw": "/(?-i:\\u{0061})b/iu",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 16,
+          "raw": "(?-i:\\u{0061})b",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 16,
+              "raw": "(?-i:\\u{0061})b",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 15,
+                  "raw": "(?-i:\\u{0061})",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 14,
+                      "raw": "\\u{0061}",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 14,
+                          "raw": "\\u{0061}",
+                          "value": 97
+                        }
+                      ]
+                    }
+                  ]
+                },
+                {
+                  "type": "Character",
+                  "parent": "♻️../..",
+                  "start": 15,
+                  "end": 16,
+                  "raw": "b",
+                  "value": 98
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 17,
+          "end": 19,
+          "raw": "iu",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": true,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-i:\\w)/ui": {
-      "error": {
-        "message": "Invalid regular expression: /(?-i:\\w)/ui: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 12,
+        "raw": "/(?-i:\\w)/ui",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?-i:\\w)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?-i:\\w)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?-i:\\w)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 8,
+                      "raw": "\\w",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 8,
+                          "raw": "\\w",
+                          "kind": "word",
+                          "negate": false
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 12,
+          "raw": "ui",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": true,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-i:\\x61)b/i": {
-      "error": {
-        "message": "Invalid regular expression: /(?-i:\\x61)b/i: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 14,
+        "raw": "/(?-i:\\x61)b/i",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 12,
+          "raw": "(?-i:\\x61)b",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 12,
+              "raw": "(?-i:\\x61)b",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 11,
+                  "raw": "(?-i:\\x61)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 10,
+                      "raw": "\\x61",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 10,
+                          "raw": "\\x61",
+                          "value": 97
+                        }
+                      ]
+                    }
+                  ]
+                },
+                {
+                  "type": "Character",
+                  "parent": "♻️../..",
+                  "start": 11,
+                  "end": 12,
+                  "raw": "b",
+                  "value": 98
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 13,
+          "end": 14,
+          "raw": "i",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-i:a(?i:b))c/i": {
-      "error": {
-        "message": "Invalid regular expression: /(?-i:a(?i:b))c/i: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 17,
+        "raw": "/(?-i:a(?i:b))c/i",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 15,
+          "raw": "(?-i:a(?i:b))c",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 15,
+              "raw": "(?-i:a(?i:b))c",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 14,
+                  "raw": "(?-i:a(?i:b))",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 13,
+                      "raw": "a(?i:b)",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "a",
+                          "value": 97
+                        },
+                        {
+                          "type": "Group",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 13,
+                          "raw": "(?i:b)",
+                          "modifiers": {
+                            "type": "Modifiers",
+                            "parent": "♻️..",
+                            "start": 9,
+                            "end": 10,
+                            "raw": "i",
+                            "add": {
+                              "type": "ModifierFlags",
+                              "parent": "♻️..",
+                              "start": 9,
+                              "end": 10,
+                              "raw": "i",
+                              "ignoreCase": true,
+                              "multiline": false,
+                              "dotAll": false
+                            },
+                            "remove": null
+                          },
+                          "alternatives": [
+                            {
+                              "type": "Alternative",
+                              "parent": "♻️../..",
+                              "start": 11,
+                              "end": 12,
+                              "raw": "b",
+                              "elements": [
+                                {
+                                  "type": "Character",
+                                  "parent": "♻️../..",
+                                  "start": 11,
+                                  "end": 12,
+                                  "raw": "b",
+                                  "value": 98
+                                }
+                              ]
+                            }
+                          ]
+                        }
+                      ]
+                    }
+                  ]
+                },
+                {
+                  "type": "Character",
+                  "parent": "♻️../..",
+                  "start": 14,
+                  "end": 15,
+                  "raw": "c",
+                  "value": 99
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 16,
+          "end": 17,
+          "raw": "i",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-i:aB)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?-i:aB)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?-i:aB)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?-i:aB)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?-i:aB)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?-i:aB)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 8,
+                      "raw": "aB",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "a",
+                          "value": 97
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "B",
+                          "value": 66
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-i:es$)/i": {
-      "error": {
-        "message": "Invalid regular expression: /(?-i:es$)/i: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 12,
+        "raw": "/(?-i:es$)/i",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 10,
+          "raw": "(?-i:es$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 10,
+              "raw": "(?-i:es$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 10,
+                  "raw": "(?-i:es$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 9,
+                      "raw": "es$",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 11,
+          "end": 12,
+          "raw": "i",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-i:es$)/im": {
-      "error": {
-        "message": "Invalid regular expression: /(?-i:es$)/im: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 13,
+        "raw": "/(?-i:es$)/im",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 10,
+          "raw": "(?-i:es$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 10,
+              "raw": "(?-i:es$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 10,
+                  "raw": "(?-i:es$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 9,
+                      "raw": "es$",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 11,
+          "end": 13,
+          "raw": "im",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": true,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-i:fo)o/i": {
-      "error": {
-        "message": "Invalid regular expression: /(?-i:fo)o/i: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 12,
+        "raw": "/(?-i:fo)o/i",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 10,
+          "raw": "(?-i:fo)o",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 10,
+              "raw": "(?-i:fo)o",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?-i:fo)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 8,
+                      "raw": "fo",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "f",
+                          "value": 102
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "o",
+                          "value": 111
+                        }
+                      ]
+                    }
+                  ]
+                },
+                {
+                  "type": "Character",
+                  "parent": "♻️../..",
+                  "start": 9,
+                  "end": 10,
+                  "raw": "o",
+                  "value": 111
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 11,
+          "end": 12,
+          "raw": "i",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-ii:a)/": {
       "error": {
-        "message": "Invalid regular expression: /(?-ii:a)/: Invalid group",
-        "index": 3
+        "message": "Invalid regular expression: /(?-ii:a)/: Duplicated flag 'i'",
+        "index": 4
       }
     },
     "/(?-im:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?-im:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?-im:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?-im:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?-im:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?-im:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "-im",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 6,
+                      "raw": "im",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 9,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-im:)/im": {
-      "error": {
-        "message": "Invalid regular expression: /(?-im:)/im: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 11,
+        "raw": "/(?-im:)/im",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?-im:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?-im:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?-im:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "-im",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 6,
+                      "raw": "im",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 11,
+          "raw": "im",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": true,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-ims:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?-ims:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?-ims:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?-ims:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?-ims:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?-ims:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "-ims",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 7,
+                      "raw": "ims",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-ims:)/ims": {
-      "error": {
-        "message": "Invalid regular expression: /(?-ims:)/ims: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 13,
+        "raw": "/(?-ims:)/ims",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?-ims:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?-ims:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?-ims:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "-ims",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 7,
+                      "raw": "ims",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 13,
+          "raw": "ims",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": true,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": true,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-imsi:a)/": {
       "error": {
-        "message": "Invalid regular expression: /(?-imsi:a)/: Invalid group",
-        "index": 3
+        "message": "Invalid regular expression: /(?-imsi:a)/: Duplicated flag 'i'",
+        "index": 4
       }
     },
     "/(?-is:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?-is:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?-is:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?-is:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?-is:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?-is:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "-is",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 6,
+                      "raw": "is",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 9,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-is:)/is": {
-      "error": {
-        "message": "Invalid regular expression: /(?-is:)/is: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 11,
+        "raw": "/(?-is:)/is",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?-is:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?-is:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?-is:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "-is",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 6,
+                      "raw": "is",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 11,
+          "raw": "is",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": true,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-ism:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?-ism:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?-ism:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?-ism:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?-ism:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?-ism:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "-ism",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 7,
+                      "raw": "ism",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-ism:)/ism": {
-      "error": {
-        "message": "Invalid regular expression: /(?-ism:)/ism: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 13,
+        "raw": "/(?-ism:)/ism",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?-ism:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?-ism:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?-ism:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "-ism",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 7,
+                      "raw": "ism",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 13,
+          "raw": "ism",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": true,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": true,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-iͥ:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?-iͥ:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?-m:(?-m:))/": {
-      "error": {
-        "message": "Invalid regular expression: /(?-m:(?-m:))/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 14,
+        "raw": "/(?-m:(?-m:))/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 13,
+          "raw": "(?-m:(?-m:))",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 13,
+              "raw": "(?-m:(?-m:))",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 13,
+                  "raw": "(?-m:(?-m:))",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-m",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 12,
+                      "raw": "(?-m:)",
+                      "elements": [
+                        {
+                          "type": "Group",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 12,
+                          "raw": "(?-m:)",
+                          "modifiers": {
+                            "type": "Modifiers",
+                            "parent": "♻️..",
+                            "start": 8,
+                            "end": 10,
+                            "raw": "-m",
+                            "add": {
+                              "type": "ModifierFlags",
+                              "parent": "♻️..",
+                              "start": 8,
+                              "end": 8,
+                              "raw": "",
+                              "ignoreCase": false,
+                              "multiline": false,
+                              "dotAll": false
+                            },
+                            "remove": {
+                              "type": "ModifierFlags",
+                              "parent": "♻️..",
+                              "start": 9,
+                              "end": 10,
+                              "raw": "m",
+                              "ignoreCase": false,
+                              "multiline": true,
+                              "dotAll": false
+                            }
+                          },
+                          "alternatives": [
+                            {
+                              "type": "Alternative",
+                              "parent": "♻️../..",
+                              "start": 11,
+                              "end": 11,
+                              "raw": "",
+                              "elements": []
+                            }
+                          ]
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 14,
+          "end": 14,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-m:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?-m:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 8,
+        "raw": "/(?-m:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 7,
+          "raw": "(?-m:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 7,
+              "raw": "(?-m:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 7,
+                  "raw": "(?-m:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-m",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 6,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 8,
+          "end": 8,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-m:)/m": {
-      "error": {
-        "message": "Invalid regular expression: /(?-m:)/m: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?-m:)/m",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 7,
+          "raw": "(?-m:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 7,
+              "raw": "(?-m:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 7,
+                  "raw": "(?-m:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-m",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 6,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 8,
+          "end": 9,
+          "raw": "m",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": true,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-m:es$)/m": {
-      "error": {
-        "message": "Invalid regular expression: /(?-m:es$)/m: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 12,
+        "raw": "/(?-m:es$)/m",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 10,
+          "raw": "(?-m:es$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 10,
+              "raw": "(?-m:es$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 10,
+                  "raw": "(?-m:es$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-m",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 9,
+                      "raw": "es$",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 11,
+          "end": 12,
+          "raw": "m",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": true,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-m:es$)/mi": {
-      "error": {
-        "message": "Invalid regular expression: /(?-m:es$)/mi: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 13,
+        "raw": "/(?-m:es$)/mi",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 10,
+          "raw": "(?-m:es$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 10,
+              "raw": "(?-m:es$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 10,
+                  "raw": "(?-m:es$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-m",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 9,
+                      "raw": "es$",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 11,
+          "end": 13,
+          "raw": "mi",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": true,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-m:es(?m-:$)|js$)/m": {
-      "error": {
-        "message": "Invalid regular expression: /(?-m:es(?m-:$)|js$)/m: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 22,
+        "raw": "/(?-m:es(?m-:$)|js$)/m",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 20,
+          "raw": "(?-m:es(?m-:$)|js$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 20,
+              "raw": "(?-m:es(?m-:$)|js$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 20,
+                  "raw": "(?-m:es(?m-:$)|js$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-m",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 15,
+                      "raw": "es(?m-:$)",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "Group",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 15,
+                          "raw": "(?m-:$)",
+                          "modifiers": {
+                            "type": "Modifiers",
+                            "parent": "♻️..",
+                            "start": 10,
+                            "end": 12,
+                            "raw": "m-",
+                            "add": {
+                              "type": "ModifierFlags",
+                              "parent": "♻️..",
+                              "start": 10,
+                              "end": 11,
+                              "raw": "m",
+                              "ignoreCase": false,
+                              "multiline": true,
+                              "dotAll": false
+                            },
+                            "remove": {
+                              "type": "ModifierFlags",
+                              "parent": "♻️..",
+                              "start": 12,
+                              "end": 12,
+                              "raw": "",
+                              "ignoreCase": false,
+                              "multiline": false,
+                              "dotAll": false
+                            }
+                          },
+                          "alternatives": [
+                            {
+                              "type": "Alternative",
+                              "parent": "♻️../..",
+                              "start": 13,
+                              "end": 14,
+                              "raw": "$",
+                              "elements": [
+                                {
+                                  "type": "Assertion",
+                                  "parent": "♻️../..",
+                                  "start": 13,
+                                  "end": 14,
+                                  "raw": "$",
+                                  "kind": "end"
+                                }
+                              ]
+                            }
+                          ]
+                        }
+                      ]
+                    },
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 16,
+                      "end": 19,
+                      "raw": "js$",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 16,
+                          "end": 17,
+                          "raw": "j",
+                          "value": 106
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 17,
+                          "end": 18,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 18,
+                          "end": 19,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 21,
+          "end": 22,
+          "raw": "m",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": true,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-m:es(?m:$)|js$)/m": {
-      "error": {
-        "message": "Invalid regular expression: /(?-m:es(?m:$)|js$)/m: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 21,
+        "raw": "/(?-m:es(?m:$)|js$)/m",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 19,
+          "raw": "(?-m:es(?m:$)|js$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 19,
+              "raw": "(?-m:es(?m:$)|js$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 19,
+                  "raw": "(?-m:es(?m:$)|js$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-m",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 14,
+                      "raw": "es(?m:$)",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "Group",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 14,
+                          "raw": "(?m:$)",
+                          "modifiers": {
+                            "type": "Modifiers",
+                            "parent": "♻️..",
+                            "start": 10,
+                            "end": 11,
+                            "raw": "m",
+                            "add": {
+                              "type": "ModifierFlags",
+                              "parent": "♻️..",
+                              "start": 10,
+                              "end": 11,
+                              "raw": "m",
+                              "ignoreCase": false,
+                              "multiline": true,
+                              "dotAll": false
+                            },
+                            "remove": null
+                          },
+                          "alternatives": [
+                            {
+                              "type": "Alternative",
+                              "parent": "♻️../..",
+                              "start": 12,
+                              "end": 13,
+                              "raw": "$",
+                              "elements": [
+                                {
+                                  "type": "Assertion",
+                                  "parent": "♻️../..",
+                                  "start": 12,
+                                  "end": 13,
+                                  "raw": "$",
+                                  "kind": "end"
+                                }
+                              ]
+                            }
+                          ]
+                        }
+                      ]
+                    },
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 15,
+                      "end": 18,
+                      "raw": "js$",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 15,
+                          "end": 16,
+                          "raw": "j",
+                          "value": 106
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 16,
+                          "end": 17,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 17,
+                          "end": 18,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 20,
+          "end": 21,
+          "raw": "m",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": true,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-m:es.$)/m": {
-      "error": {
-        "message": "Invalid regular expression: /(?-m:es.$)/m: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 13,
+        "raw": "/(?-m:es.$)/m",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 11,
+          "raw": "(?-m:es.$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 11,
+              "raw": "(?-m:es.$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 11,
+                  "raw": "(?-m:es.$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-m",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 10,
+                      "raw": "es.$",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 9,
+                          "end": 10,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 12,
+          "end": 13,
+          "raw": "m",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": true,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-m:es.$)/ms": {
-      "error": {
-        "message": "Invalid regular expression: /(?-m:es.$)/ms: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 14,
+        "raw": "/(?-m:es.$)/ms",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 11,
+          "raw": "(?-m:es.$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 11,
+              "raw": "(?-m:es.$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 11,
+                  "raw": "(?-m:es.$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-m",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 10,
+                      "raw": "es.$",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 9,
+                          "end": 10,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 12,
+          "end": 14,
+          "raw": "ms",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": true,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": true,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-mi:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?-mi:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?-mi:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?-mi:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?-mi:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?-mi:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "-mi",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 6,
+                      "raw": "mi",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 9,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-mi:)/mi": {
-      "error": {
-        "message": "Invalid regular expression: /(?-mi:)/mi: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 11,
+        "raw": "/(?-mi:)/mi",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?-mi:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?-mi:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?-mi:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "-mi",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 6,
+                      "raw": "mi",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 11,
+          "raw": "mi",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": true,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-mis:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?-mis:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?-mis:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?-mis:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?-mis:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?-mis:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "-mis",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 7,
+                      "raw": "mis",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-mis:)/mis": {
-      "error": {
-        "message": "Invalid regular expression: /(?-mis:)/mis: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 13,
+        "raw": "/(?-mis:)/mis",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?-mis:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?-mis:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?-mis:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "-mis",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 7,
+                      "raw": "mis",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 13,
+          "raw": "mis",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": true,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": true,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-ms:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?-ms:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?-ms:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?-ms:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?-ms:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?-ms:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "-ms",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 6,
+                      "raw": "ms",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 9,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-ms:)/ms": {
-      "error": {
-        "message": "Invalid regular expression: /(?-ms:)/ms: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 11,
+        "raw": "/(?-ms:)/ms",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?-ms:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?-ms:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?-ms:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "-ms",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 6,
+                      "raw": "ms",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 11,
+          "raw": "ms",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": true,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": true,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-msi:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?-msi:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?-msi:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?-msi:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?-msi:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?-msi:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "-msi",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 7,
+                      "raw": "msi",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-msi:)/msi": {
-      "error": {
-        "message": "Invalid regular expression: /(?-msi:)/msi: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 13,
+        "raw": "/(?-msi:)/msi",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?-msi:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?-msi:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?-msi:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "-msi",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 7,
+                      "raw": "msi",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 13,
+          "raw": "msi",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": true,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": true,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-mͫ:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?-mͫ:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?-s\u0000:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?-s\u0000:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?-s)/": {
       "error": {
         "message": "Invalid regular expression: /(?-s)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?-s:(?-s:))/": {
-      "error": {
-        "message": "Invalid regular expression: /(?-s:(?-s:))/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 14,
+        "raw": "/(?-s:(?-s:))/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 13,
+          "raw": "(?-s:(?-s:))",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 13,
+              "raw": "(?-s:(?-s:))",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 13,
+                  "raw": "(?-s:(?-s:))",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-s",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 12,
+                      "raw": "(?-s:)",
+                      "elements": [
+                        {
+                          "type": "Group",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 12,
+                          "raw": "(?-s:)",
+                          "modifiers": {
+                            "type": "Modifiers",
+                            "parent": "♻️..",
+                            "start": 8,
+                            "end": 10,
+                            "raw": "-s",
+                            "add": {
+                              "type": "ModifierFlags",
+                              "parent": "♻️..",
+                              "start": 8,
+                              "end": 8,
+                              "raw": "",
+                              "ignoreCase": false,
+                              "multiline": false,
+                              "dotAll": false
+                            },
+                            "remove": {
+                              "type": "ModifierFlags",
+                              "parent": "♻️..",
+                              "start": 9,
+                              "end": 10,
+                              "raw": "s",
+                              "ignoreCase": false,
+                              "multiline": false,
+                              "dotAll": true
+                            }
+                          },
+                          "alternatives": [
+                            {
+                              "type": "Alternative",
+                              "parent": "♻️../..",
+                              "start": 11,
+                              "end": 11,
+                              "raw": "",
+                              "elements": []
+                            }
+                          ]
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 14,
+          "end": 14,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-s:(?s-:^.$))/s": {
-      "error": {
-        "message": "Invalid regular expression: /(?-s:(?s-:^.$))/s: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 18,
+        "raw": "/(?-s:(?s-:^.$))/s",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 16,
+          "raw": "(?-s:(?s-:^.$))",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 16,
+              "raw": "(?-s:(?s-:^.$))",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 16,
+                  "raw": "(?-s:(?s-:^.$))",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-s",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 15,
+                      "raw": "(?s-:^.$)",
+                      "elements": [
+                        {
+                          "type": "Group",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 15,
+                          "raw": "(?s-:^.$)",
+                          "modifiers": {
+                            "type": "Modifiers",
+                            "parent": "♻️..",
+                            "start": 8,
+                            "end": 10,
+                            "raw": "s-",
+                            "add": {
+                              "type": "ModifierFlags",
+                              "parent": "♻️..",
+                              "start": 8,
+                              "end": 9,
+                              "raw": "s",
+                              "ignoreCase": false,
+                              "multiline": false,
+                              "dotAll": true
+                            },
+                            "remove": {
+                              "type": "ModifierFlags",
+                              "parent": "♻️..",
+                              "start": 10,
+                              "end": 10,
+                              "raw": "",
+                              "ignoreCase": false,
+                              "multiline": false,
+                              "dotAll": false
+                            }
+                          },
+                          "alternatives": [
+                            {
+                              "type": "Alternative",
+                              "parent": "♻️../..",
+                              "start": 11,
+                              "end": 14,
+                              "raw": "^.$",
+                              "elements": [
+                                {
+                                  "type": "Assertion",
+                                  "parent": "♻️../..",
+                                  "start": 11,
+                                  "end": 12,
+                                  "raw": "^",
+                                  "kind": "start"
+                                },
+                                {
+                                  "type": "CharacterSet",
+                                  "parent": "♻️../..",
+                                  "start": 12,
+                                  "end": 13,
+                                  "raw": ".",
+                                  "kind": "any"
+                                },
+                                {
+                                  "type": "Assertion",
+                                  "parent": "♻️../..",
+                                  "start": 13,
+                                  "end": 14,
+                                  "raw": "$",
+                                  "kind": "end"
+                                }
+                              ]
+                            }
+                          ]
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 17,
+          "end": 18,
+          "raw": "s",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": true,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-s:(?s:^.$))/s": {
-      "error": {
-        "message": "Invalid regular expression: /(?-s:(?s:^.$))/s: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 17,
+        "raw": "/(?-s:(?s:^.$))/s",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 15,
+          "raw": "(?-s:(?s:^.$))",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 15,
+              "raw": "(?-s:(?s:^.$))",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 15,
+                  "raw": "(?-s:(?s:^.$))",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-s",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 14,
+                      "raw": "(?s:^.$)",
+                      "elements": [
+                        {
+                          "type": "Group",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 14,
+                          "raw": "(?s:^.$)",
+                          "modifiers": {
+                            "type": "Modifiers",
+                            "parent": "♻️..",
+                            "start": 8,
+                            "end": 9,
+                            "raw": "s",
+                            "add": {
+                              "type": "ModifierFlags",
+                              "parent": "♻️..",
+                              "start": 8,
+                              "end": 9,
+                              "raw": "s",
+                              "ignoreCase": false,
+                              "multiline": false,
+                              "dotAll": true
+                            },
+                            "remove": null
+                          },
+                          "alternatives": [
+                            {
+                              "type": "Alternative",
+                              "parent": "♻️../..",
+                              "start": 10,
+                              "end": 13,
+                              "raw": "^.$",
+                              "elements": [
+                                {
+                                  "type": "Assertion",
+                                  "parent": "♻️../..",
+                                  "start": 10,
+                                  "end": 11,
+                                  "raw": "^",
+                                  "kind": "start"
+                                },
+                                {
+                                  "type": "CharacterSet",
+                                  "parent": "♻️../..",
+                                  "start": 11,
+                                  "end": 12,
+                                  "raw": ".",
+                                  "kind": "any"
+                                },
+                                {
+                                  "type": "Assertion",
+                                  "parent": "♻️../..",
+                                  "start": 12,
+                                  "end": 13,
+                                  "raw": "$",
+                                  "kind": "end"
+                                }
+                              ]
+                            }
+                          ]
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 16,
+          "end": 17,
+          "raw": "s",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": true,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-s:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?-s:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 8,
+        "raw": "/(?-s:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 7,
+          "raw": "(?-s:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 7,
+              "raw": "(?-s:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 7,
+                  "raw": "(?-s:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-s",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 6,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 8,
+          "end": 8,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-s:)/s": {
-      "error": {
-        "message": "Invalid regular expression: /(?-s:)/s: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?-s:)/s",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 7,
+          "raw": "(?-s:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 7,
+              "raw": "(?-s:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 7,
+                  "raw": "(?-s:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-s",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 6,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 8,
+          "end": 9,
+          "raw": "s",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": true,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-s:.es$)/s": {
-      "error": {
-        "message": "Invalid regular expression: /(?-s:.es$)/s: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 13,
+        "raw": "/(?-s:.es$)/s",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 11,
+          "raw": "(?-s:.es$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 11,
+              "raw": "(?-s:.es$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 11,
+                  "raw": "(?-s:.es$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-s",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 10,
+                      "raw": ".es$",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 9,
+                          "end": 10,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 12,
+          "end": 13,
+          "raw": "s",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": true,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-s:.es$)/sm": {
-      "error": {
-        "message": "Invalid regular expression: /(?-s:.es$)/sm: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 14,
+        "raw": "/(?-s:.es$)/sm",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 11,
+          "raw": "(?-s:.es$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 11,
+              "raw": "(?-s:.es$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 11,
+                  "raw": "(?-s:.es$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-s",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 10,
+                      "raw": ".es$",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 9,
+                          "end": 10,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 12,
+          "end": 14,
+          "raw": "sm",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": true,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": true,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-s:.es)/s": {
-      "error": {
-        "message": "Invalid regular expression: /(?-s:.es)/s: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 12,
+        "raw": "/(?-s:.es)/s",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 10,
+          "raw": "(?-s:.es)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 10,
+              "raw": "(?-s:.es)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 10,
+                  "raw": "(?-s:.es)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-s",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 9,
+                      "raw": ".es",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "s",
+                          "value": 115
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 11,
+          "end": 12,
+          "raw": "s",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": true,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-s:.es)/si": {
-      "error": {
-        "message": "Invalid regular expression: /(?-s:.es)/si: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 13,
+        "raw": "/(?-s:.es)/si",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 10,
+          "raw": "(?-s:.es)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 10,
+              "raw": "(?-s:.es)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 10,
+                  "raw": "(?-s:.es)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-s",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 9,
+                      "raw": ".es",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "s",
+                          "value": 115
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 11,
+          "end": 13,
+          "raw": "si",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": true,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-s:^.$)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?-s:^.$)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 11,
+        "raw": "/(?-s:^.$)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 10,
+          "raw": "(?-s:^.$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 10,
+              "raw": "(?-s:^.$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 10,
+                  "raw": "(?-s:^.$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-s",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 9,
+                      "raw": "^.$",
+                      "elements": [
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "^",
+                          "kind": "start"
+                        },
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 11,
+          "end": 11,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-s:^.$)/s": {
-      "error": {
-        "message": "Invalid regular expression: /(?-s:^.$)/s: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 12,
+        "raw": "/(?-s:^.$)/s",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 10,
+          "raw": "(?-s:^.$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 10,
+              "raw": "(?-s:^.$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 10,
+                  "raw": "(?-s:^.$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "-s",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 5,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 9,
+                      "raw": "^.$",
+                      "elements": [
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "^",
+                          "kind": "start"
+                        },
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 11,
+          "end": 12,
+          "raw": "s",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": true,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-si:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?-si:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?-si:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?-si:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?-si:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?-si:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "-si",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 6,
+                      "raw": "si",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 9,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-si:)/si": {
-      "error": {
-        "message": "Invalid regular expression: /(?-si:)/si: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 11,
+        "raw": "/(?-si:)/si",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?-si:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?-si:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?-si:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "-si",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 6,
+                      "raw": "si",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 11,
+          "raw": "si",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": true,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-sim:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?-sim:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?-sim:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?-sim:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?-sim:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?-sim:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "-sim",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 7,
+                      "raw": "sim",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-sim:)/sim": {
-      "error": {
-        "message": "Invalid regular expression: /(?-sim:)/sim: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 13,
+        "raw": "/(?-sim:)/sim",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?-sim:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?-sim:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?-sim:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "-sim",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 7,
+                      "raw": "sim",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 13,
+          "raw": "sim",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": true,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": true,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-sm:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?-sm:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?-sm:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?-sm:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?-sm:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?-sm:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "-sm",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 6,
+                      "raw": "sm",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 9,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-sm:)/sm": {
-      "error": {
-        "message": "Invalid regular expression: /(?-sm:)/sm: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 11,
+        "raw": "/(?-sm:)/sm",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?-sm:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?-sm:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?-sm:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "-sm",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 6,
+                      "raw": "sm",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 11,
+          "raw": "sm",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": true,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": true,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-smi:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?-smi:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?-smi:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?-smi:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?-smi:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?-smi:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "-smi",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 7,
+                      "raw": "smi",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-smi:)/smi": {
-      "error": {
-        "message": "Invalid regular expression: /(?-smi:)/smi: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 13,
+        "raw": "/(?-smi:)/smi",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?-smi:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?-smi:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?-smi:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "-smi",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 3,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 7,
+                      "raw": "smi",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 13,
+          "raw": "smi",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": true,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": true,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?-s̀:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?-s̀:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?-s‌:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?-s‌:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?-s‍:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?-s‍:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?-s‎:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?-s‎:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?-s:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?-s:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?-u:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?-u:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?-y:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?-y:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?-İ:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?-İ:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?-ſ:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?-ſ:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?1-:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?1-:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?1:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?1:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?I-:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?I-:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?I:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?I:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?M-:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?M-:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?M:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?M:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?Q-:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?Q-:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?Q:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?Q:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?S-:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?S-:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?S:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?S:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?\\u0069:a)/u": {
       "error": {
         "message": "Invalid regular expression: /(?\\u0069:a)/u: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?\\u006D:a)/u": {
       "error": {
         "message": "Invalid regular expression: /(?\\u006D:a)/u: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?\\u0073:a)/u": {
       "error": {
         "message": "Invalid regular expression: /(?\\u0073:a)/u: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?\\u{0073}-s:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?\\u{0073}-s:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?d-:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?d-:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?d:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?d:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?g-:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?g-:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?g:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?g:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?i-)/": {
       "error": {
         "message": "Invalid regular expression: /(?i-)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?i-:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?i-:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 8,
+        "raw": "/(?i-:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 7,
+          "raw": "(?i-:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 7,
+              "raw": "(?i-:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 7,
+                  "raw": "(?i-:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "i-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 6,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 8,
+          "end": 8,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i-:.es)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?i-:.es)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 11,
+        "raw": "/(?i-:.es)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 10,
+          "raw": "(?i-:.es)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 10,
+              "raw": "(?i-:.es)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 10,
+                  "raw": "(?i-:.es)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "i-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 9,
+                      "raw": ".es",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "s",
+                          "value": 115
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 11,
+          "end": 11,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i-:.es)/s": {
-      "error": {
-        "message": "Invalid regular expression: /(?i-:.es)/s: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 12,
+        "raw": "/(?i-:.es)/s",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 10,
+          "raw": "(?i-:.es)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 10,
+              "raw": "(?i-:.es)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 10,
+                  "raw": "(?i-:.es)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "i-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 9,
+                      "raw": ".es",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "s",
+                          "value": 115
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 11,
+          "end": 12,
+          "raw": "s",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": true,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i-:Z\\B)/u": {
-      "error": {
-        "message": "Invalid regular expression: /(?i-:Z\\B)/u: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 12,
+        "raw": "/(?i-:Z\\B)/u",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 10,
+          "raw": "(?i-:Z\\B)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 10,
+              "raw": "(?i-:Z\\B)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 10,
+                  "raw": "(?i-:Z\\B)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "i-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 9,
+                      "raw": "Z\\B",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "Z",
+                          "value": 90
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 9,
+                          "raw": "\\B",
+                          "kind": "word",
+                          "negate": true
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 11,
+          "end": 12,
+          "raw": "u",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": true,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i-:[^ab])c/": {
-      "error": {
-        "message": "Invalid regular expression: /(?i-:[^ab])c/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 14,
+        "raw": "/(?i-:[^ab])c/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 13,
+          "raw": "(?i-:[^ab])c",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 13,
+              "raw": "(?i-:[^ab])c",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 12,
+                  "raw": "(?i-:[^ab])",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "i-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 11,
+                      "raw": "[^ab]",
+                      "elements": [
+                        {
+                          "type": "CharacterClass",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 11,
+                          "raw": "[^ab]",
+                          "unicodeSets": false,
+                          "negate": true,
+                          "elements": [
+                            {
+                              "type": "Character",
+                              "parent": "♻️../..",
+                              "start": 8,
+                              "end": 9,
+                              "raw": "a",
+                              "value": 97
+                            },
+                            {
+                              "type": "Character",
+                              "parent": "♻️../..",
+                              "start": 9,
+                              "end": 10,
+                              "raw": "b",
+                              "value": 98
+                            }
+                          ]
+                        }
+                      ]
+                    }
+                  ]
+                },
+                {
+                  "type": "Character",
+                  "parent": "♻️../..",
+                  "start": 12,
+                  "end": 13,
+                  "raw": "c",
+                  "value": 99
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 14,
+          "end": 14,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i-:[ab])c/": {
-      "error": {
-        "message": "Invalid regular expression: /(?i-:[ab])c/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 13,
+        "raw": "/(?i-:[ab])c/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 12,
+          "raw": "(?i-:[ab])c",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 12,
+              "raw": "(?i-:[ab])c",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 11,
+                  "raw": "(?i-:[ab])",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "i-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 10,
+                      "raw": "[ab]",
+                      "elements": [
+                        {
+                          "type": "CharacterClass",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 10,
+                          "raw": "[ab]",
+                          "unicodeSets": false,
+                          "negate": false,
+                          "elements": [
+                            {
+                              "type": "Character",
+                              "parent": "♻️../..",
+                              "start": 7,
+                              "end": 8,
+                              "raw": "a",
+                              "value": 97
+                            },
+                            {
+                              "type": "Character",
+                              "parent": "♻️../..",
+                              "start": 8,
+                              "end": 9,
+                              "raw": "b",
+                              "value": 98
+                            }
+                          ]
+                        }
+                      ]
+                    }
+                  ]
+                },
+                {
+                  "type": "Character",
+                  "parent": "♻️../..",
+                  "start": 11,
+                  "end": 12,
+                  "raw": "c",
+                  "value": 99
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 13,
+          "end": 13,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i-:\\P{Lu})/u": {
-      "error": {
-        "message": "Invalid regular expression: /(?i-:\\P{Lu})/u: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 15,
+        "raw": "/(?i-:\\P{Lu})/u",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 13,
+          "raw": "(?i-:\\P{Lu})",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 13,
+              "raw": "(?i-:\\P{Lu})",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 13,
+                  "raw": "(?i-:\\P{Lu})",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "i-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 12,
+                      "raw": "\\P{Lu}",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 12,
+                          "raw": "\\P{Lu}",
+                          "kind": "property",
+                          "strings": false,
+                          "key": "General_Category",
+                          "value": "Lu",
+                          "negate": true
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 14,
+          "end": 15,
+          "raw": "u",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": true,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i-:\\W)/u": {
-      "error": {
-        "message": "Invalid regular expression: /(?i-:\\W)/u: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 11,
+        "raw": "/(?i-:\\W)/u",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?i-:\\W)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?i-:\\W)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?i-:\\W)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "i-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 8,
+                      "raw": "\\W",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 8,
+                          "raw": "\\W",
+                          "kind": "word",
+                          "negate": true
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 11,
+          "raw": "u",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": true,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i-:\\b)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?i-:\\b)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?i-:\\b)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?i-:\\b)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?i-:\\b)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?i-:\\b)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "i-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 8,
+                      "raw": "\\b",
+                      "elements": [
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 8,
+                          "raw": "\\b",
+                          "kind": "word",
+                          "negate": false
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i-:\\b)/u": {
-      "error": {
-        "message": "Invalid regular expression: /(?i-:\\b)/u: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 11,
+        "raw": "/(?i-:\\b)/u",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?i-:\\b)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?i-:\\b)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?i-:\\b)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "i-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 8,
+                      "raw": "\\b",
+                      "elements": [
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 8,
+                          "raw": "\\b",
+                          "kind": "word",
+                          "negate": false
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 11,
+          "raw": "u",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": true,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i-:\\p{Lu})/u": {
-      "error": {
-        "message": "Invalid regular expression: /(?i-:\\p{Lu})/u: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 15,
+        "raw": "/(?i-:\\p{Lu})/u",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 13,
+          "raw": "(?i-:\\p{Lu})",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 13,
+              "raw": "(?i-:\\p{Lu})",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 13,
+                  "raw": "(?i-:\\p{Lu})",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "i-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 12,
+                      "raw": "\\p{Lu}",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 12,
+                          "raw": "\\p{Lu}",
+                          "kind": "property",
+                          "strings": false,
+                          "key": "General_Category",
+                          "value": "Lu",
+                          "negate": false
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 14,
+          "end": 15,
+          "raw": "u",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": true,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i-:\\u0061)b/": {
-      "error": {
-        "message": "Invalid regular expression: /(?i-:\\u0061)b/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 15,
+        "raw": "/(?i-:\\u0061)b/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 14,
+          "raw": "(?i-:\\u0061)b",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 14,
+              "raw": "(?i-:\\u0061)b",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 13,
+                  "raw": "(?i-:\\u0061)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "i-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 12,
+                      "raw": "\\u0061",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 12,
+                          "raw": "\\u0061",
+                          "value": 97
+                        }
+                      ]
+                    }
+                  ]
+                },
+                {
+                  "type": "Character",
+                  "parent": "♻️../..",
+                  "start": 13,
+                  "end": 14,
+                  "raw": "b",
+                  "value": 98
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 15,
+          "end": 15,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i-:\\u{0061})b/u": {
-      "error": {
-        "message": "Invalid regular expression: /(?i-:\\u{0061})b/u: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 18,
+        "raw": "/(?i-:\\u{0061})b/u",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 16,
+          "raw": "(?i-:\\u{0061})b",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 16,
+              "raw": "(?i-:\\u{0061})b",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 15,
+                  "raw": "(?i-:\\u{0061})",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "i-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 14,
+                      "raw": "\\u{0061}",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 14,
+                          "raw": "\\u{0061}",
+                          "value": 97
+                        }
+                      ]
+                    }
+                  ]
+                },
+                {
+                  "type": "Character",
+                  "parent": "♻️../..",
+                  "start": 15,
+                  "end": 16,
+                  "raw": "b",
+                  "value": 98
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 17,
+          "end": 18,
+          "raw": "u",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": true,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i-:\\w)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?i-:\\w)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?i-:\\w)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?i-:\\w)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?i-:\\w)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?i-:\\w)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "i-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 8,
+                      "raw": "\\w",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 8,
+                          "raw": "\\w",
+                          "kind": "word",
+                          "negate": false
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i-:\\w)/u": {
-      "error": {
-        "message": "Invalid regular expression: /(?i-:\\w)/u: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 11,
+        "raw": "/(?i-:\\w)/u",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?i-:\\w)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?i-:\\w)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?i-:\\w)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "i-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 8,
+                      "raw": "\\w",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 8,
+                          "raw": "\\w",
+                          "kind": "word",
+                          "negate": false
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 11,
+          "raw": "u",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": true,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i-:\\x61)b/": {
-      "error": {
-        "message": "Invalid regular expression: /(?i-:\\x61)b/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 13,
+        "raw": "/(?i-:\\x61)b/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 12,
+          "raw": "(?i-:\\x61)b",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 12,
+              "raw": "(?i-:\\x61)b",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 11,
+                  "raw": "(?i-:\\x61)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "i-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 10,
+                      "raw": "\\x61",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 10,
+                          "raw": "\\x61",
+                          "value": 97
+                        }
+                      ]
+                    }
+                  ]
+                },
+                {
+                  "type": "Character",
+                  "parent": "♻️../..",
+                  "start": 11,
+                  "end": 12,
+                  "raw": "b",
+                  "value": 98
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 13,
+          "end": 13,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i-:es$)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?i-:es$)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 11,
+        "raw": "/(?i-:es$)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 10,
+          "raw": "(?i-:es$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 10,
+              "raw": "(?i-:es$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 10,
+                  "raw": "(?i-:es$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "i-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 9,
+                      "raw": "es$",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 11,
+          "end": 11,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i-:es$)/m": {
-      "error": {
-        "message": "Invalid regular expression: /(?i-:es$)/m: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 12,
+        "raw": "/(?i-:es$)/m",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 10,
+          "raw": "(?i-:es$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 10,
+              "raw": "(?i-:es$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 10,
+                  "raw": "(?i-:es$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "i-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 9,
+                      "raw": "es$",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 11,
+          "end": 12,
+          "raw": "m",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": true,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i-i:a)/": {
       "error": {
-        "message": "Invalid regular expression: /(?i-i:a)/: Invalid group",
-        "index": 3
+        "message": "Invalid regular expression: /(?i-i:a)/: Duplicated flag 'i'",
+        "index": 6
       }
     },
     "/(?i-m:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?i-m:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?i-m:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?i-m:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?i-m:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?i-m:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "i-m",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 6,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 9,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i-ms:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?i-ms:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?i-ms:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?i-ms:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?i-ms:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?i-ms:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "i-ms",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 7,
+                      "raw": "ms",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i-s:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?i-s:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?i-s:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?i-s:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?i-s:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?i-s:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "i-s",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 6,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 9,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i-sm:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?i-sm:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?i-sm:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?i-sm:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?i-sm:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?i-sm:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "i-sm",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 7,
+                      "raw": "sm",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i:(?i:))/": {
-      "error": {
-        "message": "Invalid regular expression: /(?i:(?i:))/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 12,
+        "raw": "/(?i:(?i:))/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 11,
+          "raw": "(?i:(?i:))",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 11,
+              "raw": "(?i:(?i:))",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 11,
+                  "raw": "(?i:(?i:))",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 10,
+                      "raw": "(?i:)",
+                      "elements": [
+                        {
+                          "type": "Group",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 10,
+                          "raw": "(?i:)",
+                          "modifiers": {
+                            "type": "Modifiers",
+                            "parent": "♻️..",
+                            "start": 7,
+                            "end": 8,
+                            "raw": "i",
+                            "add": {
+                              "type": "ModifierFlags",
+                              "parent": "♻️..",
+                              "start": 7,
+                              "end": 8,
+                              "raw": "i",
+                              "ignoreCase": true,
+                              "multiline": false,
+                              "dotAll": false
+                            },
+                            "remove": null
+                          },
+                          "alternatives": [
+                            {
+                              "type": "Alternative",
+                              "parent": "♻️../..",
+                              "start": 9,
+                              "end": 9,
+                              "raw": "",
+                              "elements": []
+                            }
+                          ]
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 12,
+          "end": 12,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?i:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 7,
+        "raw": "/(?i:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 6,
+          "raw": "(?i:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 6,
+              "raw": "(?i:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 6,
+                  "raw": "(?i:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 7,
+          "end": 7,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i:)/i": {
-      "error": {
-        "message": "Invalid regular expression: /(?i:)/i: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 8,
+        "raw": "/(?i:)/i",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 6,
+          "raw": "(?i:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 6,
+              "raw": "(?i:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 6,
+                  "raw": "(?i:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 7,
+          "end": 8,
+          "raw": "i",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i:.es)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?i:.es)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?i:.es)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?i:.es)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?i:.es)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?i:.es)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 8,
+                      "raw": ".es",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 6,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "s",
+                          "value": 115
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i:.es)/s": {
-      "error": {
-        "message": "Invalid regular expression: /(?i:.es)/s: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 11,
+        "raw": "/(?i:.es)/s",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?i:.es)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?i:.es)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?i:.es)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 8,
+                      "raw": ".es",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 6,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "s",
+                          "value": 115
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 11,
+          "raw": "s",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": true,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i:Z\\B)/u": {
-      "error": {
-        "message": "Invalid regular expression: /(?i:Z\\B)/u: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 11,
+        "raw": "/(?i:Z\\B)/u",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?i:Z\\B)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?i:Z\\B)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?i:Z\\B)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 8,
+                      "raw": "Z\\B",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 6,
+                          "raw": "Z",
+                          "value": 90
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 8,
+                          "raw": "\\B",
+                          "kind": "word",
+                          "negate": true
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 11,
+          "raw": "u",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": true,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i:[^ab])c/": {
-      "error": {
-        "message": "Invalid regular expression: /(?i:[^ab])c/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 13,
+        "raw": "/(?i:[^ab])c/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 12,
+          "raw": "(?i:[^ab])c",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 12,
+              "raw": "(?i:[^ab])c",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 11,
+                  "raw": "(?i:[^ab])",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 10,
+                      "raw": "[^ab]",
+                      "elements": [
+                        {
+                          "type": "CharacterClass",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 10,
+                          "raw": "[^ab]",
+                          "unicodeSets": false,
+                          "negate": true,
+                          "elements": [
+                            {
+                              "type": "Character",
+                              "parent": "♻️../..",
+                              "start": 7,
+                              "end": 8,
+                              "raw": "a",
+                              "value": 97
+                            },
+                            {
+                              "type": "Character",
+                              "parent": "♻️../..",
+                              "start": 8,
+                              "end": 9,
+                              "raw": "b",
+                              "value": 98
+                            }
+                          ]
+                        }
+                      ]
+                    }
+                  ]
+                },
+                {
+                  "type": "Character",
+                  "parent": "♻️../..",
+                  "start": 11,
+                  "end": 12,
+                  "raw": "c",
+                  "value": 99
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 13,
+          "end": 13,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i:[ab])c/": {
-      "error": {
-        "message": "Invalid regular expression: /(?i:[ab])c/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 12,
+        "raw": "/(?i:[ab])c/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 11,
+          "raw": "(?i:[ab])c",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 11,
+              "raw": "(?i:[ab])c",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 10,
+                  "raw": "(?i:[ab])",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 9,
+                      "raw": "[ab]",
+                      "elements": [
+                        {
+                          "type": "CharacterClass",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 9,
+                          "raw": "[ab]",
+                          "unicodeSets": false,
+                          "negate": false,
+                          "elements": [
+                            {
+                              "type": "Character",
+                              "parent": "♻️../..",
+                              "start": 6,
+                              "end": 7,
+                              "raw": "a",
+                              "value": 97
+                            },
+                            {
+                              "type": "Character",
+                              "parent": "♻️../..",
+                              "start": 7,
+                              "end": 8,
+                              "raw": "b",
+                              "value": 98
+                            }
+                          ]
+                        }
+                      ]
+                    }
+                  ]
+                },
+                {
+                  "type": "Character",
+                  "parent": "♻️../..",
+                  "start": 10,
+                  "end": 11,
+                  "raw": "c",
+                  "value": 99
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 12,
+          "end": 12,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i:\\P{Lu})/u": {
-      "error": {
-        "message": "Invalid regular expression: /(?i:\\P{Lu})/u: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 14,
+        "raw": "/(?i:\\P{Lu})/u",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 12,
+          "raw": "(?i:\\P{Lu})",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 12,
+              "raw": "(?i:\\P{Lu})",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 12,
+                  "raw": "(?i:\\P{Lu})",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 11,
+                      "raw": "\\P{Lu}",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 11,
+                          "raw": "\\P{Lu}",
+                          "kind": "property",
+                          "strings": false,
+                          "key": "General_Category",
+                          "value": "Lu",
+                          "negate": true
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 13,
+          "end": 14,
+          "raw": "u",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": true,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i:\\W)/u": {
-      "error": {
-        "message": "Invalid regular expression: /(?i:\\W)/u: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?i:\\W)/u",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?i:\\W)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?i:\\W)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?i:\\W)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 7,
+                      "raw": "\\W",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 7,
+                          "raw": "\\W",
+                          "kind": "word",
+                          "negate": true
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 10,
+          "raw": "u",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": true,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i:\\b)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?i:\\b)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?i:\\b)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?i:\\b)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?i:\\b)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?i:\\b)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 7,
+                      "raw": "\\b",
+                      "elements": [
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 7,
+                          "raw": "\\b",
+                          "kind": "word",
+                          "negate": false
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 9,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i:\\b)/u": {
-      "error": {
-        "message": "Invalid regular expression: /(?i:\\b)/u: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?i:\\b)/u",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?i:\\b)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?i:\\b)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?i:\\b)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 7,
+                      "raw": "\\b",
+                      "elements": [
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 7,
+                          "raw": "\\b",
+                          "kind": "word",
+                          "negate": false
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 10,
+          "raw": "u",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": true,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i:\\p{Lu})/u": {
-      "error": {
-        "message": "Invalid regular expression: /(?i:\\p{Lu})/u: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 14,
+        "raw": "/(?i:\\p{Lu})/u",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 12,
+          "raw": "(?i:\\p{Lu})",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 12,
+              "raw": "(?i:\\p{Lu})",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 12,
+                  "raw": "(?i:\\p{Lu})",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 11,
+                      "raw": "\\p{Lu}",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 11,
+                          "raw": "\\p{Lu}",
+                          "kind": "property",
+                          "strings": false,
+                          "key": "General_Category",
+                          "value": "Lu",
+                          "negate": false
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 13,
+          "end": 14,
+          "raw": "u",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": true,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i:\\u0061)b/": {
-      "error": {
-        "message": "Invalid regular expression: /(?i:\\u0061)b/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 14,
+        "raw": "/(?i:\\u0061)b/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 13,
+          "raw": "(?i:\\u0061)b",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 13,
+              "raw": "(?i:\\u0061)b",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 12,
+                  "raw": "(?i:\\u0061)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 11,
+                      "raw": "\\u0061",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 11,
+                          "raw": "\\u0061",
+                          "value": 97
+                        }
+                      ]
+                    }
+                  ]
+                },
+                {
+                  "type": "Character",
+                  "parent": "♻️../..",
+                  "start": 12,
+                  "end": 13,
+                  "raw": "b",
+                  "value": 98
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 14,
+          "end": 14,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i:\\u{0061})b/u": {
-      "error": {
-        "message": "Invalid regular expression: /(?i:\\u{0061})b/u: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 17,
+        "raw": "/(?i:\\u{0061})b/u",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 15,
+          "raw": "(?i:\\u{0061})b",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 15,
+              "raw": "(?i:\\u{0061})b",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 14,
+                  "raw": "(?i:\\u{0061})",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 13,
+                      "raw": "\\u{0061}",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 13,
+                          "raw": "\\u{0061}",
+                          "value": 97
+                        }
+                      ]
+                    }
+                  ]
+                },
+                {
+                  "type": "Character",
+                  "parent": "♻️../..",
+                  "start": 14,
+                  "end": 15,
+                  "raw": "b",
+                  "value": 98
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 16,
+          "end": 17,
+          "raw": "u",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": true,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i:\\w)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?i:\\w)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?i:\\w)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?i:\\w)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?i:\\w)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?i:\\w)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 7,
+                      "raw": "\\w",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 7,
+                          "raw": "\\w",
+                          "kind": "word",
+                          "negate": false
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 9,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i:\\w)/u": {
-      "error": {
-        "message": "Invalid regular expression: /(?i:\\w)/u: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?i:\\w)/u",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?i:\\w)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?i:\\w)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?i:\\w)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 7,
+                      "raw": "\\w",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 7,
+                          "raw": "\\w",
+                          "kind": "word",
+                          "negate": false
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 10,
+          "raw": "u",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": true,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i:\\x61)b/": {
-      "error": {
-        "message": "Invalid regular expression: /(?i:\\x61)b/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 12,
+        "raw": "/(?i:\\x61)b/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 11,
+          "raw": "(?i:\\x61)b",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 11,
+              "raw": "(?i:\\x61)b",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 10,
+                  "raw": "(?i:\\x61)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 9,
+                      "raw": "\\x61",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 9,
+                          "raw": "\\x61",
+                          "value": 97
+                        }
+                      ]
+                    }
+                  ]
+                },
+                {
+                  "type": "Character",
+                  "parent": "♻️../..",
+                  "start": 10,
+                  "end": 11,
+                  "raw": "b",
+                  "value": 98
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 12,
+          "end": 12,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i:a)b/": {
-      "error": {
-        "message": "Invalid regular expression: /(?i:a)b/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?i:a)b/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?i:a)b",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?i:a)b",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 7,
+                  "raw": "(?i:a)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 6,
+                      "raw": "a",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 6,
+                          "raw": "a",
+                          "value": 97
+                        }
+                      ]
+                    }
+                  ]
+                },
+                {
+                  "type": "Character",
+                  "parent": "♻️../..",
+                  "start": 7,
+                  "end": 8,
+                  "raw": "b",
+                  "value": 98
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 9,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i:aB)/i": {
-      "error": {
-        "message": "Invalid regular expression: /(?i:aB)/i: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?i:aB)/i",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?i:aB)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?i:aB)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?i:aB)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 7,
+                      "raw": "aB",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 6,
+                          "raw": "a",
+                          "value": 97
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "B",
+                          "value": 66
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 10,
+          "raw": "i",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i:es$)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?i:es$)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?i:es$)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?i:es$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?i:es$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?i:es$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 8,
+                      "raw": "es$",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 6,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?i:es$)/m": {
-      "error": {
-        "message": "Invalid regular expression: /(?i:es$)/m: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 11,
+        "raw": "/(?i:es$)/m",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?i:es$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?i:es$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?i:es$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 8,
+                      "raw": "es$",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 6,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 11,
+          "raw": "m",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": true,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?ii-:a)/": {
       "error": {
-        "message": "Invalid regular expression: /(?ii-:a)/: Invalid group",
+        "message": "Invalid regular expression: /(?ii-:a)/: Duplicated flag 'i'",
         "index": 3
       }
     },
     "/(?ii:a)/": {
       "error": {
-        "message": "Invalid regular expression: /(?ii:a)/: Invalid group",
+        "message": "Invalid regular expression: /(?ii:a)/: Duplicated flag 'i'",
         "index": 3
       }
     },
     "/(?im-:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?im-:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?im-:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?im-:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?im-:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?im-:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "im-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 5,
+                      "raw": "im",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 6,
+                      "end": 6,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 9,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?im-s:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?im-s:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?im-s:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?im-s:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?im-s:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?im-s:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "im-s",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 5,
+                      "raw": "im",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 6,
+                      "end": 7,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?im:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?im:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 8,
+        "raw": "/(?im:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 7,
+          "raw": "(?im:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 7,
+              "raw": "(?im:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 7,
+                  "raw": "(?im:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "im",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 5,
+                      "raw": "im",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 6,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 8,
+          "end": 8,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?ims-:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?ims-:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?ims-:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?ims-:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?ims-:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?ims-:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "ims-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 6,
+                      "raw": "ims",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": true
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?ims-m:a)/": {
       "error": {
-        "message": "Invalid regular expression: /(?ims-m:a)/: Invalid group",
-        "index": 3
+        "message": "Invalid regular expression: /(?ims-m:a)/: Duplicated flag 'm'",
+        "index": 8
       }
     },
     "/(?ims:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?ims:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?ims:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?ims:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?ims:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?ims:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "ims",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 6,
+                      "raw": "ims",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": true
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 9,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?ims:)/ims": {
-      "error": {
-        "message": "Invalid regular expression: /(?ims:)/ims: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 12,
+        "raw": "/(?ims:)/ims",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?ims:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?ims:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?ims:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "ims",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 6,
+                      "raw": "ims",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": true
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 12,
+          "raw": "ims",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": true,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": true,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?imsi-:a)/": {
       "error": {
-        "message": "Invalid regular expression: /(?imsi-:a)/: Invalid group",
+        "message": "Invalid regular expression: /(?imsi-:a)/: Duplicated flag 'i'",
         "index": 3
       }
     },
     "/(?imsi:a)/": {
       "error": {
-        "message": "Invalid regular expression: /(?imsi:a)/: Invalid group",
+        "message": "Invalid regular expression: /(?imsi:a)/: Duplicated flag 'i'",
         "index": 3
       }
     },
     "/(?is-:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?is-:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?is-:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?is-:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?is-:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?is-:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "is-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 5,
+                      "raw": "is",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": true
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 6,
+                      "end": 6,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 9,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?is-m:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?is-m:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?is-m:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?is-m:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?is-m:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?is-m:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "is-m",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 5,
+                      "raw": "is",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": true
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 6,
+                      "end": 7,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?is:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?is:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 8,
+        "raw": "/(?is:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 7,
+          "raw": "(?is:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 7,
+              "raw": "(?is:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 7,
+                  "raw": "(?is:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "is",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 5,
+                      "raw": "is",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": true
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 6,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 8,
+          "end": 8,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?ism-:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?ism-:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?ism-:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?ism-:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?ism-:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?ism-:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "ism-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 6,
+                      "raw": "ism",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": true
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?ism:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?ism:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?ism:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?ism:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?ism:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?ism:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "ism",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 6,
+                      "raw": "ism",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": true
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 9,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?iͥ-:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?iͥ-:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?iͥ:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?iͥ:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?m-:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?m-:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 8,
+        "raw": "/(?m-:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 7,
+          "raw": "(?m-:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 7,
+              "raw": "(?m-:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 7,
+                  "raw": "(?m-:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "m-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 6,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 8,
+          "end": 8,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?m-:es$)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?m-:es$)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 11,
+        "raw": "/(?m-:es$)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 10,
+          "raw": "(?m-:es$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 10,
+              "raw": "(?m-:es$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 10,
+                  "raw": "(?m-:es$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "m-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 9,
+                      "raw": "es$",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 11,
+          "end": 11,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?m-:es$)/i": {
-      "error": {
-        "message": "Invalid regular expression: /(?m-:es$)/i: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 12,
+        "raw": "/(?m-:es$)/i",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 10,
+          "raw": "(?m-:es$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 10,
+              "raw": "(?m-:es$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 10,
+                  "raw": "(?m-:es$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "m-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 9,
+                      "raw": "es$",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 11,
+          "end": 12,
+          "raw": "i",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?m-:es$|(?-m:js$))/": {
-      "error": {
-        "message": "Invalid regular expression: /(?m-:es$|(?-m:js$))/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 21,
+        "raw": "/(?m-:es$|(?-m:js$))/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 20,
+          "raw": "(?m-:es$|(?-m:js$))",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 20,
+              "raw": "(?m-:es$|(?-m:js$))",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 20,
+                  "raw": "(?m-:es$|(?-m:js$))",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "m-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 9,
+                      "raw": "es$",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    },
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 10,
+                      "end": 19,
+                      "raw": "(?-m:js$)",
+                      "elements": [
+                        {
+                          "type": "Group",
+                          "parent": "♻️../..",
+                          "start": 10,
+                          "end": 19,
+                          "raw": "(?-m:js$)",
+                          "modifiers": {
+                            "type": "Modifiers",
+                            "parent": "♻️..",
+                            "start": 12,
+                            "end": 14,
+                            "raw": "-m",
+                            "add": {
+                              "type": "ModifierFlags",
+                              "parent": "♻️..",
+                              "start": 12,
+                              "end": 12,
+                              "raw": "",
+                              "ignoreCase": false,
+                              "multiline": false,
+                              "dotAll": false
+                            },
+                            "remove": {
+                              "type": "ModifierFlags",
+                              "parent": "♻️..",
+                              "start": 13,
+                              "end": 14,
+                              "raw": "m",
+                              "ignoreCase": false,
+                              "multiline": true,
+                              "dotAll": false
+                            }
+                          },
+                          "alternatives": [
+                            {
+                              "type": "Alternative",
+                              "parent": "♻️../..",
+                              "start": 15,
+                              "end": 18,
+                              "raw": "js$",
+                              "elements": [
+                                {
+                                  "type": "Character",
+                                  "parent": "♻️../..",
+                                  "start": 15,
+                                  "end": 16,
+                                  "raw": "j",
+                                  "value": 106
+                                },
+                                {
+                                  "type": "Character",
+                                  "parent": "♻️../..",
+                                  "start": 16,
+                                  "end": 17,
+                                  "raw": "s",
+                                  "value": 115
+                                },
+                                {
+                                  "type": "Assertion",
+                                  "parent": "♻️../..",
+                                  "start": 17,
+                                  "end": 18,
+                                  "raw": "$",
+                                  "kind": "end"
+                                }
+                              ]
+                            }
+                          ]
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 21,
+          "end": 21,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?m-:es.$)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?m-:es.$)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 12,
+        "raw": "/(?m-:es.$)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 11,
+          "raw": "(?m-:es.$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 11,
+              "raw": "(?m-:es.$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 11,
+                  "raw": "(?m-:es.$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "m-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 10,
+                      "raw": "es.$",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 9,
+                          "end": 10,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 12,
+          "end": 12,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?m-:es.$)/s": {
-      "error": {
-        "message": "Invalid regular expression: /(?m-:es.$)/s: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 13,
+        "raw": "/(?m-:es.$)/s",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 11,
+          "raw": "(?m-:es.$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 11,
+              "raw": "(?m-:es.$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 11,
+                  "raw": "(?m-:es.$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "m-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 10,
+                      "raw": "es.$",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 9,
+                          "end": 10,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 12,
+          "end": 13,
+          "raw": "s",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": true,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?m-i:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?m-i:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?m-i:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?m-i:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?m-i:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?m-i:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "m-i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 6,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 9,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?m-i:^a$)/i": {
-      "error": {
-        "message": "Invalid regular expression: /(?m-i:^a$)/i: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 13,
+        "raw": "/(?m-i:^a$)/i",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 11,
+          "raw": "(?m-i:^a$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 11,
+              "raw": "(?m-i:^a$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 11,
+                  "raw": "(?m-i:^a$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "m-i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 6,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 10,
+                      "raw": "^a$",
+                      "elements": [
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "^",
+                          "kind": "start"
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "a",
+                          "value": 97
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 9,
+                          "end": 10,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 12,
+          "end": 13,
+          "raw": "i",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?m-ims:a)/": {
       "error": {
-        "message": "Invalid regular expression: /(?m-ims:a)/: Invalid group",
-        "index": 3
+        "message": "Invalid regular expression: /(?m-ims:a)/: Duplicated flag 'm'",
+        "index": 8
       }
     },
     "/(?m-is:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?m-is:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?m-is:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?m-is:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?m-is:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?m-is:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "m-is",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 7,
+                      "raw": "is",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?m-m:a)/": {
       "error": {
-        "message": "Invalid regular expression: /(?m-m:a)/: Invalid group",
-        "index": 3
+        "message": "Invalid regular expression: /(?m-m:a)/: Duplicated flag 'm'",
+        "index": 6
       }
     },
     "/(?m-s:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?m-s:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?m-s:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?m-s:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?m-s:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?m-s:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "m-s",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 6,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 9,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?m-si:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?m-si:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?m-si:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?m-si:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?m-si:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?m-si:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "m-si",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 7,
+                      "raw": "si",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?m:(?m:))/": {
-      "error": {
-        "message": "Invalid regular expression: /(?m:(?m:))/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 12,
+        "raw": "/(?m:(?m:))/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 11,
+          "raw": "(?m:(?m:))",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 11,
+              "raw": "(?m:(?m:))",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 11,
+                  "raw": "(?m:(?m:))",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "m",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 10,
+                      "raw": "(?m:)",
+                      "elements": [
+                        {
+                          "type": "Group",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 10,
+                          "raw": "(?m:)",
+                          "modifiers": {
+                            "type": "Modifiers",
+                            "parent": "♻️..",
+                            "start": 7,
+                            "end": 8,
+                            "raw": "m",
+                            "add": {
+                              "type": "ModifierFlags",
+                              "parent": "♻️..",
+                              "start": 7,
+                              "end": 8,
+                              "raw": "m",
+                              "ignoreCase": false,
+                              "multiline": true,
+                              "dotAll": false
+                            },
+                            "remove": null
+                          },
+                          "alternatives": [
+                            {
+                              "type": "Alternative",
+                              "parent": "♻️../..",
+                              "start": 9,
+                              "end": 9,
+                              "raw": "",
+                              "elements": []
+                            }
+                          ]
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 12,
+          "end": 12,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?m:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?m:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 7,
+        "raw": "/(?m:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 6,
+          "raw": "(?m:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 6,
+              "raw": "(?m:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 6,
+                  "raw": "(?m:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "m",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 7,
+          "end": 7,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?m:)/m": {
-      "error": {
-        "message": "Invalid regular expression: /(?m:)/m: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 8,
+        "raw": "/(?m:)/m",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 6,
+          "raw": "(?m:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 6,
+              "raw": "(?m:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 6,
+                  "raw": "(?m:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "m",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 7,
+          "end": 8,
+          "raw": "m",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": true,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?m:^(?-i:a)$)/i": {
-      "error": {
-        "message": "Invalid regular expression: /(?m:^(?-i:a)$)/i: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 17,
+        "raw": "/(?m:^(?-i:a)$)/i",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 15,
+          "raw": "(?m:^(?-i:a)$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 15,
+              "raw": "(?m:^(?-i:a)$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 15,
+                  "raw": "(?m:^(?-i:a)$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "m",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 14,
+                      "raw": "^(?-i:a)$",
+                      "elements": [
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 6,
+                          "raw": "^",
+                          "kind": "start"
+                        },
+                        {
+                          "type": "Group",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 13,
+                          "raw": "(?-i:a)",
+                          "modifiers": {
+                            "type": "Modifiers",
+                            "parent": "♻️..",
+                            "start": 8,
+                            "end": 10,
+                            "raw": "-i",
+                            "add": {
+                              "type": "ModifierFlags",
+                              "parent": "♻️..",
+                              "start": 8,
+                              "end": 8,
+                              "raw": "",
+                              "ignoreCase": false,
+                              "multiline": false,
+                              "dotAll": false
+                            },
+                            "remove": {
+                              "type": "ModifierFlags",
+                              "parent": "♻️..",
+                              "start": 9,
+                              "end": 10,
+                              "raw": "i",
+                              "ignoreCase": true,
+                              "multiline": false,
+                              "dotAll": false
+                            }
+                          },
+                          "alternatives": [
+                            {
+                              "type": "Alternative",
+                              "parent": "♻️../..",
+                              "start": 11,
+                              "end": 12,
+                              "raw": "a",
+                              "elements": [
+                                {
+                                  "type": "Character",
+                                  "parent": "♻️../..",
+                                  "start": 11,
+                                  "end": 12,
+                                  "raw": "a",
+                                  "value": 97
+                                }
+                              ]
+                            }
+                          ]
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 13,
+                          "end": 14,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 16,
+          "end": 17,
+          "raw": "i",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?m:es$)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?m:es$)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?m:es$)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?m:es$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?m:es$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?m:es$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "m",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 8,
+                      "raw": "es$",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 6,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?m:es$)/i": {
-      "error": {
-        "message": "Invalid regular expression: /(?m:es$)/i: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 11,
+        "raw": "/(?m:es$)/i",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?m:es$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?m:es$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?m:es$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "m",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 8,
+                      "raw": "es$",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 6,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 11,
+          "raw": "i",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?m:es$)/m": {
-      "error": {
-        "message": "Invalid regular expression: /(?m:es$)/m: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 11,
+        "raw": "/(?m:es$)/m",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?m:es$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?m:es$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?m:es$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "m",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 8,
+                      "raw": "es$",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 6,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 11,
+          "raw": "m",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": true,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?m:es$|(?-m:js$))/": {
-      "error": {
-        "message": "Invalid regular expression: /(?m:es$|(?-m:js$))/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 20,
+        "raw": "/(?m:es$|(?-m:js$))/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 19,
+          "raw": "(?m:es$|(?-m:js$))",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 19,
+              "raw": "(?m:es$|(?-m:js$))",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 19,
+                  "raw": "(?m:es$|(?-m:js$))",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "m",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 8,
+                      "raw": "es$",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 6,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    },
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 9,
+                      "end": 18,
+                      "raw": "(?-m:js$)",
+                      "elements": [
+                        {
+                          "type": "Group",
+                          "parent": "♻️../..",
+                          "start": 9,
+                          "end": 18,
+                          "raw": "(?-m:js$)",
+                          "modifiers": {
+                            "type": "Modifiers",
+                            "parent": "♻️..",
+                            "start": 11,
+                            "end": 13,
+                            "raw": "-m",
+                            "add": {
+                              "type": "ModifierFlags",
+                              "parent": "♻️..",
+                              "start": 11,
+                              "end": 11,
+                              "raw": "",
+                              "ignoreCase": false,
+                              "multiline": false,
+                              "dotAll": false
+                            },
+                            "remove": {
+                              "type": "ModifierFlags",
+                              "parent": "♻️..",
+                              "start": 12,
+                              "end": 13,
+                              "raw": "m",
+                              "ignoreCase": false,
+                              "multiline": true,
+                              "dotAll": false
+                            }
+                          },
+                          "alternatives": [
+                            {
+                              "type": "Alternative",
+                              "parent": "♻️../..",
+                              "start": 14,
+                              "end": 17,
+                              "raw": "js$",
+                              "elements": [
+                                {
+                                  "type": "Character",
+                                  "parent": "♻️../..",
+                                  "start": 14,
+                                  "end": 15,
+                                  "raw": "j",
+                                  "value": 106
+                                },
+                                {
+                                  "type": "Character",
+                                  "parent": "♻️../..",
+                                  "start": 15,
+                                  "end": 16,
+                                  "raw": "s",
+                                  "value": 115
+                                },
+                                {
+                                  "type": "Assertion",
+                                  "parent": "♻️../..",
+                                  "start": 16,
+                                  "end": 17,
+                                  "raw": "$",
+                                  "kind": "end"
+                                }
+                              ]
+                            }
+                          ]
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 20,
+          "end": 20,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?m:es.$)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?m:es.$)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 11,
+        "raw": "/(?m:es.$)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 10,
+          "raw": "(?m:es.$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 10,
+              "raw": "(?m:es.$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 10,
+                  "raw": "(?m:es.$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "m",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 9,
+                      "raw": "es.$",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 6,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 11,
+          "end": 11,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?m:es.$)/s": {
-      "error": {
-        "message": "Invalid regular expression: /(?m:es.$)/s: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 12,
+        "raw": "/(?m:es.$)/s",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 10,
+          "raw": "(?m:es.$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 10,
+              "raw": "(?m:es.$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 10,
+                  "raw": "(?m:es.$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "m",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 9,
+                      "raw": "es.$",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 6,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 11,
+          "end": 12,
+          "raw": "s",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": true,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?mi-:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?mi-:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?mi-:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?mi-:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?mi-:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?mi-:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "mi-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 5,
+                      "raw": "mi",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 6,
+                      "end": 6,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 9,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?mi-s:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?mi-s:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?mi-s:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?mi-s:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?mi-s:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?mi-s:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "mi-s",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 5,
+                      "raw": "mi",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 6,
+                      "end": 7,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?mi:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?mi:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 8,
+        "raw": "/(?mi:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 7,
+          "raw": "(?mi:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 7,
+              "raw": "(?mi:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 7,
+                  "raw": "(?mi:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "mi",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 5,
+                      "raw": "mi",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 6,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 8,
+          "end": 8,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?mis-:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?mis-:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?mis-:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?mis-:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?mis-:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?mis-:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "mis-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 6,
+                      "raw": "mis",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": true
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?mis:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?mis:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?mis:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?mis:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?mis:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?mis:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "mis",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 6,
+                      "raw": "mis",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": true
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 9,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?ms-:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?ms-:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?ms-:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?ms-:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?ms-:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?ms-:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "ms-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 5,
+                      "raw": "ms",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": true
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 6,
+                      "end": 6,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 9,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?ms-i)/": {
       "error": {
         "message": "Invalid regular expression: /(?ms-i)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?ms-i:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?ms-i:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?ms-i:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?ms-i:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?ms-i:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?ms-i:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "ms-i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 5,
+                      "raw": "ms",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": true
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 6,
+                      "end": 7,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?ms:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?ms:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 8,
+        "raw": "/(?ms:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 7,
+          "raw": "(?ms:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 7,
+              "raw": "(?ms:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 7,
+                  "raw": "(?ms:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "ms",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 5,
+                      "raw": "ms",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": true
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 6,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 8,
+          "end": 8,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?msi-:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?msi-:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?msi-:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?msi-:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?msi-:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?msi-:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "msi-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 6,
+                      "raw": "msi",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": true
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?msi:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?msi:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?msi:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?msi:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?msi:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?msi:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "msi",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 6,
+                      "raw": "msi",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": true
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 9,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?mͫ-:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?mͫ-:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?mͫ:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?mͫ:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?s\u0000-:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?s\u0000-:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?s\u0000:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?s\u0000:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?s-:(?-s:^.$))/": {
-      "error": {
-        "message": "Invalid regular expression: /(?s-:(?-s:^.$))/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 17,
+        "raw": "/(?s-:(?-s:^.$))/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 16,
+          "raw": "(?s-:(?-s:^.$))",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 16,
+              "raw": "(?s-:(?-s:^.$))",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 16,
+                  "raw": "(?s-:(?-s:^.$))",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "s-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 15,
+                      "raw": "(?-s:^.$)",
+                      "elements": [
+                        {
+                          "type": "Group",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 15,
+                          "raw": "(?-s:^.$)",
+                          "modifiers": {
+                            "type": "Modifiers",
+                            "parent": "♻️..",
+                            "start": 8,
+                            "end": 10,
+                            "raw": "-s",
+                            "add": {
+                              "type": "ModifierFlags",
+                              "parent": "♻️..",
+                              "start": 8,
+                              "end": 8,
+                              "raw": "",
+                              "ignoreCase": false,
+                              "multiline": false,
+                              "dotAll": false
+                            },
+                            "remove": {
+                              "type": "ModifierFlags",
+                              "parent": "♻️..",
+                              "start": 9,
+                              "end": 10,
+                              "raw": "s",
+                              "ignoreCase": false,
+                              "multiline": false,
+                              "dotAll": true
+                            }
+                          },
+                          "alternatives": [
+                            {
+                              "type": "Alternative",
+                              "parent": "♻️../..",
+                              "start": 11,
+                              "end": 14,
+                              "raw": "^.$",
+                              "elements": [
+                                {
+                                  "type": "Assertion",
+                                  "parent": "♻️../..",
+                                  "start": 11,
+                                  "end": 12,
+                                  "raw": "^",
+                                  "kind": "start"
+                                },
+                                {
+                                  "type": "CharacterSet",
+                                  "parent": "♻️../..",
+                                  "start": 12,
+                                  "end": 13,
+                                  "raw": ".",
+                                  "kind": "any"
+                                },
+                                {
+                                  "type": "Assertion",
+                                  "parent": "♻️../..",
+                                  "start": 13,
+                                  "end": 14,
+                                  "raw": "$",
+                                  "kind": "end"
+                                }
+                              ]
+                            }
+                          ]
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 17,
+          "end": 17,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?s-:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?s-:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 8,
+        "raw": "/(?s-:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 7,
+          "raw": "(?s-:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 7,
+              "raw": "(?s-:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 7,
+                  "raw": "(?s-:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "s-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 6,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 8,
+          "end": 8,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?s-:.es$)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?s-:.es$)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 12,
+        "raw": "/(?s-:.es$)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 11,
+          "raw": "(?s-:.es$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 11,
+              "raw": "(?s-:.es$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 11,
+                  "raw": "(?s-:.es$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "s-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 10,
+                      "raw": ".es$",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 9,
+                          "end": 10,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 12,
+          "end": 12,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?s-:.es$)/m": {
-      "error": {
-        "message": "Invalid regular expression: /(?s-:.es$)/m: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 13,
+        "raw": "/(?s-:.es$)/m",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 11,
+          "raw": "(?s-:.es$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 11,
+              "raw": "(?s-:.es$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 11,
+                  "raw": "(?s-:.es$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "s-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 10,
+                      "raw": ".es$",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 9,
+                          "end": 10,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 12,
+          "end": 13,
+          "raw": "m",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": true,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?s-:.es)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?s-:.es)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 11,
+        "raw": "/(?s-:.es)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 10,
+          "raw": "(?s-:.es)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 10,
+              "raw": "(?s-:.es)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 10,
+                  "raw": "(?s-:.es)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "s-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 9,
+                      "raw": ".es",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "s",
+                          "value": 115
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 11,
+          "end": 11,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?s-:.es)/i": {
-      "error": {
-        "message": "Invalid regular expression: /(?s-:.es)/i: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 12,
+        "raw": "/(?s-:.es)/i",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 10,
+          "raw": "(?s-:.es)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 10,
+              "raw": "(?s-:.es)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 10,
+                  "raw": "(?s-:.es)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "s-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 9,
+                      "raw": ".es",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "s",
+                          "value": 115
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 11,
+          "end": 12,
+          "raw": "i",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?s-:^.$)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?s-:^.$)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 11,
+        "raw": "/(?s-:^.$)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 10,
+          "raw": "(?s-:^.$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 10,
+              "raw": "(?s-:^.$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 10,
+                  "raw": "(?s-:^.$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "s-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 9,
+                      "raw": "^.$",
+                      "elements": [
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "^",
+                          "kind": "start"
+                        },
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 11,
+          "end": 11,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?s-\\u{0073}:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?s-\\u{0073}:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?s-i:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?s-i:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?s-i:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?s-i:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?s-i:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?s-i:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "s-i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 6,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 9,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?s-im:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?s-im:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?s-im:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?s-im:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?s-im:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?s-im:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "s-im",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 7,
+                      "raw": "im",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?s-m:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?s-m:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?s-m:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?s-m:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?s-m:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?s-m:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "s-m",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 6,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 9,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?s-mi:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?s-mi:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?s-mi:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?s-mi:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?s-mi:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?s-mi:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "s-mi",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 7,
+                      "raw": "mi",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?s-s:a)/": {
       "error": {
-        "message": "Invalid regular expression: /(?s-s:a)/: Invalid group",
-        "index": 3
+        "message": "Invalid regular expression: /(?s-s:a)/: Duplicated flag 's'",
+        "index": 6
       }
     },
     "/(?s:(?-s:^.$))/": {
-      "error": {
-        "message": "Invalid regular expression: /(?s:(?-s:^.$))/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 16,
+        "raw": "/(?s:(?-s:^.$))/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 15,
+          "raw": "(?s:(?-s:^.$))",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 15,
+              "raw": "(?s:(?-s:^.$))",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 15,
+                  "raw": "(?s:(?-s:^.$))",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "s",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 14,
+                      "raw": "(?-s:^.$)",
+                      "elements": [
+                        {
+                          "type": "Group",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 14,
+                          "raw": "(?-s:^.$)",
+                          "modifiers": {
+                            "type": "Modifiers",
+                            "parent": "♻️..",
+                            "start": 7,
+                            "end": 9,
+                            "raw": "-s",
+                            "add": {
+                              "type": "ModifierFlags",
+                              "parent": "♻️..",
+                              "start": 7,
+                              "end": 7,
+                              "raw": "",
+                              "ignoreCase": false,
+                              "multiline": false,
+                              "dotAll": false
+                            },
+                            "remove": {
+                              "type": "ModifierFlags",
+                              "parent": "♻️..",
+                              "start": 8,
+                              "end": 9,
+                              "raw": "s",
+                              "ignoreCase": false,
+                              "multiline": false,
+                              "dotAll": true
+                            }
+                          },
+                          "alternatives": [
+                            {
+                              "type": "Alternative",
+                              "parent": "♻️../..",
+                              "start": 10,
+                              "end": 13,
+                              "raw": "^.$",
+                              "elements": [
+                                {
+                                  "type": "Assertion",
+                                  "parent": "♻️../..",
+                                  "start": 10,
+                                  "end": 11,
+                                  "raw": "^",
+                                  "kind": "start"
+                                },
+                                {
+                                  "type": "CharacterSet",
+                                  "parent": "♻️../..",
+                                  "start": 11,
+                                  "end": 12,
+                                  "raw": ".",
+                                  "kind": "any"
+                                },
+                                {
+                                  "type": "Assertion",
+                                  "parent": "♻️../..",
+                                  "start": 12,
+                                  "end": 13,
+                                  "raw": "$",
+                                  "kind": "end"
+                                }
+                              ]
+                            }
+                          ]
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 16,
+          "end": 16,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?s:(?s:))/": {
-      "error": {
-        "message": "Invalid regular expression: /(?s:(?s:))/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 12,
+        "raw": "/(?s:(?s:))/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 11,
+          "raw": "(?s:(?s:))",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 11,
+              "raw": "(?s:(?s:))",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 11,
+                  "raw": "(?s:(?s:))",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "s",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 10,
+                      "raw": "(?s:)",
+                      "elements": [
+                        {
+                          "type": "Group",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 10,
+                          "raw": "(?s:)",
+                          "modifiers": {
+                            "type": "Modifiers",
+                            "parent": "♻️..",
+                            "start": 7,
+                            "end": 8,
+                            "raw": "s",
+                            "add": {
+                              "type": "ModifierFlags",
+                              "parent": "♻️..",
+                              "start": 7,
+                              "end": 8,
+                              "raw": "s",
+                              "ignoreCase": false,
+                              "multiline": false,
+                              "dotAll": true
+                            },
+                            "remove": null
+                          },
+                          "alternatives": [
+                            {
+                              "type": "Alternative",
+                              "parent": "♻️../..",
+                              "start": 9,
+                              "end": 9,
+                              "raw": "",
+                              "elements": []
+                            }
+                          ]
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 12,
+          "end": 12,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?s:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?s:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 7,
+        "raw": "/(?s:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 6,
+          "raw": "(?s:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 6,
+              "raw": "(?s:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 6,
+                  "raw": "(?s:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "s",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 7,
+          "end": 7,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?s:)/s": {
-      "error": {
-        "message": "Invalid regular expression: /(?s:)/s: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 8,
+        "raw": "/(?s:)/s",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 6,
+          "raw": "(?s:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 6,
+              "raw": "(?s:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 6,
+                  "raw": "(?s:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "s",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 5,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 7,
+          "end": 8,
+          "raw": "s",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": true,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?s:.es$)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?s:.es$)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 11,
+        "raw": "/(?s:.es$)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 10,
+          "raw": "(?s:.es$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 10,
+              "raw": "(?s:.es$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 10,
+                  "raw": "(?s:.es$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "s",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 9,
+                      "raw": ".es$",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 6,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 11,
+          "end": 11,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?s:.es$)/m": {
-      "error": {
-        "message": "Invalid regular expression: /(?s:.es$)/m: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 12,
+        "raw": "/(?s:.es$)/m",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 10,
+          "raw": "(?s:.es$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 10,
+              "raw": "(?s:.es$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 10,
+                  "raw": "(?s:.es$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "s",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 9,
+                      "raw": ".es$",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 6,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 11,
+          "end": 12,
+          "raw": "m",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": true,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?s:.es)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?s:.es)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?s:.es)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?s:.es)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?s:.es)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?s:.es)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "s",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 8,
+                      "raw": ".es",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 6,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "s",
+                          "value": 115
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?s:.es)/i": {
-      "error": {
-        "message": "Invalid regular expression: /(?s:.es)/i: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 11,
+        "raw": "/(?s:.es)/i",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?s:.es)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?s:.es)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?s:.es)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "s",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 8,
+                      "raw": ".es",
+                      "elements": [
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 6,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "s",
+                          "value": 115
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 11,
+          "raw": "i",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?s:^.$)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?s:^.$)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?s:^.$)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?s:^.$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?s:^.$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?s:^.$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "s",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 8,
+                      "raw": "^.$",
+                      "elements": [
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 6,
+                          "raw": "^",
+                          "kind": "start"
+                        },
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?s:^.$)/s": {
-      "error": {
-        "message": "Invalid regular expression: /(?s:^.$)/s: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 11,
+        "raw": "/(?s:^.$)/s",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?s:^.$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?s:^.$)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?s:^.$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 4,
+                    "raw": "s",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 4,
+                      "raw": "s",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": true
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 5,
+                      "end": 8,
+                      "raw": "^.$",
+                      "elements": [
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 5,
+                          "end": 6,
+                          "raw": "^",
+                          "kind": "start"
+                        },
+                        {
+                          "type": "CharacterSet",
+                          "parent": "♻️../..",
+                          "start": 6,
+                          "end": 7,
+                          "raw": ".",
+                          "kind": "any"
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 11,
+          "raw": "s",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": true,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?si-:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?si-:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?si-:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?si-:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?si-:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?si-:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "si-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 5,
+                      "raw": "si",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": true
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 6,
+                      "end": 6,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 9,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?si-m:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?si-m:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?si-m:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?si-m:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?si-m:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?si-m:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "si-m",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 5,
+                      "raw": "si",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": true
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 6,
+                      "end": 7,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?si:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?si:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 8,
+        "raw": "/(?si:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 7,
+          "raw": "(?si:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 7,
+              "raw": "(?si:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 7,
+                  "raw": "(?si:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "si",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 5,
+                      "raw": "si",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": true
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 6,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 8,
+          "end": 8,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?sim-:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?sim-:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?sim-:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?sim-:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?sim-:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?sim-:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "sim-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 6,
+                      "raw": "sim",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": true
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?sim:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?sim:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?sim:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?sim:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?sim:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?sim:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "sim",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 6,
+                      "raw": "sim",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": true
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 9,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?sm-:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?sm-:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?sm-:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?sm-:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?sm-:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?sm-:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "sm-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 5,
+                      "raw": "sm",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": true
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 6,
+                      "end": 6,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 9,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?sm-i:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?sm-i:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?sm-i:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?sm-i:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?sm-i:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?sm-i:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "sm-i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 5,
+                      "raw": "sm",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": true
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 6,
+                      "end": 7,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?sm:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?sm:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 8,
+        "raw": "/(?sm:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 7,
+          "raw": "(?sm:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 7,
+              "raw": "(?sm:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 7,
+                  "raw": "(?sm:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 5,
+                    "raw": "sm",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 5,
+                      "raw": "sm",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": true
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 6,
+                      "end": 6,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 8,
+          "end": 8,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?smi-:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?smi-:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 10,
+        "raw": "/(?smi-:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 9,
+          "raw": "(?smi-:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 9,
+              "raw": "(?smi-:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 9,
+                  "raw": "(?smi-:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 7,
+                    "raw": "smi-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 6,
+                      "raw": "smi",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": true
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 10,
+          "end": 10,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?smi:)/": {
-      "error": {
-        "message": "Invalid regular expression: /(?smi:)/: Invalid group",
-        "index": 3
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 9,
+        "raw": "/(?smi:)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 8,
+          "raw": "(?smi:)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 8,
+              "raw": "(?smi:)",
+              "elements": [
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 8,
+                  "raw": "(?smi:)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 3,
+                    "end": 6,
+                    "raw": "smi",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 3,
+                      "end": 6,
+                      "raw": "smi",
+                      "ignoreCase": true,
+                      "multiline": true,
+                      "dotAll": true
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 7,
+                      "raw": "",
+                      "elements": []
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 9,
+          "end": 9,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(?s̀-:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?s̀-:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?s̀:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?s̀:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?s‌-:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?s‌-:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?s‌:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?s‌:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?s‍-:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?s‍-:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?s‍:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?s‍:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?s‎-:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?s‎-:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?s‎:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?s‎:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?s-:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?s-:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?s:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?s:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?u-:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?u-:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?u:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?u:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?y-:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?y-:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?y:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?y:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?İ-:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?İ-:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?İ:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?İ:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?ſ-:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?ſ-:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(?ſ:a)/": {
       "error": {
         "message": "Invalid regular expression: /(?ſ:a)/: Invalid group",
-        "index": 3
+        "index": 2
       }
     },
     "/(a)(?-i:\\1)/i": {
-      "error": {
-        "message": "Invalid regular expression: /(a)(?-i:\\1)/i: Invalid group",
-        "index": 6
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 14,
+        "raw": "/(a)(?-i:\\1)/i",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 12,
+          "raw": "(a)(?-i:\\1)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 12,
+              "raw": "(a)(?-i:\\1)",
+              "elements": [
+                {
+                  "type": "CapturingGroup",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 4,
+                  "raw": "(a)",
+                  "name": null,
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 2,
+                      "end": 3,
+                      "raw": "a",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 2,
+                          "end": 3,
+                          "raw": "a",
+                          "value": 97
+                        }
+                      ]
+                    }
+                  ],
+                  "references": [
+                    "♻️../1/alternatives/0/elements/0"
+                  ]
+                },
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 4,
+                  "end": 12,
+                  "raw": "(?-i:\\1)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 6,
+                    "end": 8,
+                    "raw": "-i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 6,
+                      "end": 6,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 7,
+                      "end": 8,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 9,
+                      "end": 11,
+                      "raw": "\\1",
+                      "elements": [
+                        {
+                          "type": "Backreference",
+                          "parent": "♻️../..",
+                          "start": 9,
+                          "end": 11,
+                          "raw": "\\1",
+                          "ref": 1,
+                          "ambiguous": false,
+                          "resolved": "♻️../../../../../0"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 13,
+          "end": 14,
+          "raw": "i",
+          "global": false,
+          "ignoreCase": true,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(a)(?i-:\\1)/": {
-      "error": {
-        "message": "Invalid regular expression: /(a)(?i-:\\1)/: Invalid group",
-        "index": 6
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 13,
+        "raw": "/(a)(?i-:\\1)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 12,
+          "raw": "(a)(?i-:\\1)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 12,
+              "raw": "(a)(?i-:\\1)",
+              "elements": [
+                {
+                  "type": "CapturingGroup",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 4,
+                  "raw": "(a)",
+                  "name": null,
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 2,
+                      "end": 3,
+                      "raw": "a",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 2,
+                          "end": 3,
+                          "raw": "a",
+                          "value": 97
+                        }
+                      ]
+                    }
+                  ],
+                  "references": [
+                    "♻️../1/alternatives/0/elements/0"
+                  ]
+                },
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 4,
+                  "end": 12,
+                  "raw": "(?i-:\\1)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 6,
+                    "end": 8,
+                    "raw": "i-",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 6,
+                      "end": 7,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 8,
+                      "end": 8,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 9,
+                      "end": 11,
+                      "raw": "\\1",
+                      "elements": [
+                        {
+                          "type": "Backreference",
+                          "parent": "♻️../..",
+                          "start": 9,
+                          "end": 11,
+                          "raw": "\\1",
+                          "ref": 1,
+                          "ambiguous": false,
+                          "resolved": "♻️../../../../../0"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 13,
+          "end": 13,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/(a)(?i:\\1)/": {
-      "error": {
-        "message": "Invalid regular expression: /(a)(?i:\\1)/: Invalid group",
-        "index": 6
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 12,
+        "raw": "/(a)(?i:\\1)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 11,
+          "raw": "(a)(?i:\\1)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 11,
+              "raw": "(a)(?i:\\1)",
+              "elements": [
+                {
+                  "type": "CapturingGroup",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 4,
+                  "raw": "(a)",
+                  "name": null,
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 2,
+                      "end": 3,
+                      "raw": "a",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 2,
+                          "end": 3,
+                          "raw": "a",
+                          "value": 97
+                        }
+                      ]
+                    }
+                  ],
+                  "references": [
+                    "♻️../1/alternatives/0/elements/0"
+                  ]
+                },
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 4,
+                  "end": 11,
+                  "raw": "(?i:\\1)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 6,
+                    "end": 7,
+                    "raw": "i",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 6,
+                      "end": 7,
+                      "raw": "i",
+                      "ignoreCase": true,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": null
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 8,
+                      "end": 10,
+                      "raw": "\\1",
+                      "elements": [
+                        {
+                          "type": "Backreference",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 10,
+                          "raw": "\\1",
+                          "ref": 1,
+                          "ambiguous": false,
+                          "resolved": "♻️../../../../../0"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 12,
+          "end": 12,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/^(?-m:es$)/": {
-      "error": {
-        "message": "Invalid regular expression: /^(?-m:es$)/: Invalid group",
-        "index": 4
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 12,
+        "raw": "/^(?-m:es$)/",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 11,
+          "raw": "^(?-m:es$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 11,
+              "raw": "^(?-m:es$)",
+              "elements": [
+                {
+                  "type": "Assertion",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 2,
+                  "raw": "^",
+                  "kind": "start"
+                },
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 2,
+                  "end": 11,
+                  "raw": "(?-m:es$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 4,
+                    "end": 6,
+                    "raw": "-m",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 4,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 6,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 10,
+                      "raw": "es$",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 9,
+                          "end": 10,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 12,
+          "end": 12,
+          "raw": "",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": false,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     },
     "/^(?-m:es$)/m": {
-      "error": {
-        "message": "Invalid regular expression: /^(?-m:es$)/m: Invalid group",
-        "index": 4
+      "ast": {
+        "type": "RegExpLiteral",
+        "parent": null,
+        "start": 0,
+        "end": 13,
+        "raw": "/^(?-m:es$)/m",
+        "pattern": {
+          "type": "Pattern",
+          "parent": "♻️..",
+          "start": 1,
+          "end": 11,
+          "raw": "^(?-m:es$)",
+          "alternatives": [
+            {
+              "type": "Alternative",
+              "parent": "♻️../..",
+              "start": 1,
+              "end": 11,
+              "raw": "^(?-m:es$)",
+              "elements": [
+                {
+                  "type": "Assertion",
+                  "parent": "♻️../..",
+                  "start": 1,
+                  "end": 2,
+                  "raw": "^",
+                  "kind": "start"
+                },
+                {
+                  "type": "Group",
+                  "parent": "♻️../..",
+                  "start": 2,
+                  "end": 11,
+                  "raw": "(?-m:es$)",
+                  "modifiers": {
+                    "type": "Modifiers",
+                    "parent": "♻️..",
+                    "start": 4,
+                    "end": 6,
+                    "raw": "-m",
+                    "add": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 4,
+                      "end": 4,
+                      "raw": "",
+                      "ignoreCase": false,
+                      "multiline": false,
+                      "dotAll": false
+                    },
+                    "remove": {
+                      "type": "ModifierFlags",
+                      "parent": "♻️..",
+                      "start": 5,
+                      "end": 6,
+                      "raw": "m",
+                      "ignoreCase": false,
+                      "multiline": true,
+                      "dotAll": false
+                    }
+                  },
+                  "alternatives": [
+                    {
+                      "type": "Alternative",
+                      "parent": "♻️../..",
+                      "start": 7,
+                      "end": 10,
+                      "raw": "es$",
+                      "elements": [
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 7,
+                          "end": 8,
+                          "raw": "e",
+                          "value": 101
+                        },
+                        {
+                          "type": "Character",
+                          "parent": "♻️../..",
+                          "start": 8,
+                          "end": 9,
+                          "raw": "s",
+                          "value": 115
+                        },
+                        {
+                          "type": "Assertion",
+                          "parent": "♻️../..",
+                          "start": 9,
+                          "end": 10,
+                          "raw": "$",
+                          "kind": "end"
+                        }
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        },
+        "flags": {
+          "type": "Flags",
+          "parent": "♻️..",
+          "start": 12,
+          "end": 13,
+          "raw": "m",
+          "global": false,
+          "ignoreCase": false,
+          "multiline": true,
+          "unicode": false,
+          "sticky": false,
+          "dotAll": false,
+          "hasIndices": false,
+          "unicodeSets": false
+        }
       }
     }
   }
diff --git a/test/fixtures/visitor/full.json b/test/fixtures/visitor/full.json
index 6c435c0..02fb207 100644
--- a/test/fixtures/visitor/full.json
+++ b/test/fixtures/visitor/full.json
@@ -8138,6 +8138,112 @@
       "enter:Flags:v",
       "leave:Flags:v",
       "leave:RegExpLiteral:/[\\q{a|bc|def}]/v"
+    ],
+    "/(?i-m:p)/": [
+      "enter:RegExpLiteral:/(?i-m:p)/",
+      "enter:Pattern:(?i-m:p)",
+      "enter:Alternative:(?i-m:p)",
+      "enter:Group:(?i-m:p)",
+      "enter:Modifiers:i-m",
+      "enter:ModifierFlags:i",
+      "leave:ModifierFlags:i",
+      "enter:ModifierFlags:m",
+      "leave:ModifierFlags:m",
+      "leave:Modifiers:i-m",
+      "enter:Alternative:p",
+      "enter:Character:p",
+      "leave:Character:p",
+      "leave:Alternative:p",
+      "leave:Group:(?i-m:p)",
+      "leave:Alternative:(?i-m:p)",
+      "leave:Pattern:(?i-m:p)",
+      "enter:Flags:",
+      "leave:Flags:",
+      "leave:RegExpLiteral:/(?i-m:p)/"
+    ],
+    "/(?ims:p)/u": [
+      "enter:RegExpLiteral:/(?ims:p)/u",
+      "enter:Pattern:(?ims:p)",
+      "enter:Alternative:(?ims:p)",
+      "enter:Group:(?ims:p)",
+      "enter:Modifiers:ims",
+      "enter:ModifierFlags:ims",
+      "leave:ModifierFlags:ims",
+      "leave:Modifiers:ims",
+      "enter:Alternative:p",
+      "enter:Character:p",
+      "leave:Character:p",
+      "leave:Alternative:p",
+      "leave:Group:(?ims:p)",
+      "leave:Alternative:(?ims:p)",
+      "leave:Pattern:(?ims:p)",
+      "enter:Flags:u",
+      "leave:Flags:u",
+      "leave:RegExpLiteral:/(?ims:p)/u"
+    ],
+    "/(?-ims:p)?/": [
+      "enter:RegExpLiteral:/(?-ims:p)?/",
+      "enter:Pattern:(?-ims:p)?",
+      "enter:Alternative:(?-ims:p)?",
+      "enter:Quantifier:(?-ims:p)?",
+      "enter:Group:(?-ims:p)",
+      "enter:Modifiers:-ims",
+      "enter:ModifierFlags:",
+      "leave:ModifierFlags:",
+      "enter:ModifierFlags:ims",
+      "leave:ModifierFlags:ims",
+      "leave:Modifiers:-ims",
+      "enter:Alternative:p",
+      "enter:Character:p",
+      "leave:Character:p",
+      "leave:Alternative:p",
+      "leave:Group:(?-ims:p)",
+      "leave:Quantifier:(?-ims:p)?",
+      "leave:Alternative:(?-ims:p)?",
+      "leave:Pattern:(?-ims:p)?",
+      "enter:Flags:",
+      "leave:Flags:",
+      "leave:RegExpLiteral:/(?-ims:p)?/"
+    ],
+    "/(?:no-modifiers)?/": [
+      "enter:RegExpLiteral:/(?:no-modifiers)?/",
+      "enter:Pattern:(?:no-modifiers)?",
+      "enter:Alternative:(?:no-modifiers)?",
+      "enter:Quantifier:(?:no-modifiers)?",
+      "enter:Group:(?:no-modifiers)",
+      "enter:Alternative:no-modifiers",
+      "enter:Character:n",
+      "leave:Character:n",
+      "enter:Character:o",
+      "leave:Character:o",
+      "enter:Character:-",
+      "leave:Character:-",
+      "enter:Character:m",
+      "leave:Character:m",
+      "enter:Character:o",
+      "leave:Character:o",
+      "enter:Character:d",
+      "leave:Character:d",
+      "enter:Character:i",
+      "leave:Character:i",
+      "enter:Character:f",
+      "leave:Character:f",
+      "enter:Character:i",
+      "leave:Character:i",
+      "enter:Character:e",
+      "leave:Character:e",
+      "enter:Character:r",
+      "leave:Character:r",
+      "enter:Character:s",
+      "leave:Character:s",
+      "leave:Alternative:no-modifiers",
+      "leave:Group:(?:no-modifiers)",
+      "leave:Quantifier:(?:no-modifiers)?",
+      "leave:Alternative:(?:no-modifiers)?",
+      "leave:Pattern:(?:no-modifiers)?",
+      "enter:Flags:",
+      "leave:Flags:",
+      "leave:RegExpLiteral:/(?:no-modifiers)?/"
     ]
   }
 }
\ No newline at end of file
diff --git a/test/visitor.ts b/test/visitor.ts
index c59f7c4..92fa77e 100644
--- a/test/visitor.ts
+++ b/test/visitor.ts
@@ -41,6 +41,8 @@ describe("visitRegExpAST function:", () => {
                         onExpressionCharacterClassEnter: enter,
                         onFlagsEnter: enter,
                         onGroupEnter: enter,
+                        onModifierFlagsEnter: enter,
+                        onModifiersEnter: enter,
                         onPatternEnter: enter,
                         onQuantifierEnter: enter,
                         onRegExpLiteralEnter: enter,
@@ -59,6 +61,8 @@ describe("visitRegExpAST function:", () => {
                         onExpressionCharacterClassLeave: leave,
                         onFlagsLeave: leave,
                         onGroupLeave: leave,
+                        onModifierFlagsLeave: leave,
+                        onModifiersLeave: leave,
                         onPatternLeave: leave,
                         onQuantifierLeave: leave,
                         onRegExpLiteralLeave: leave,
diff --git a/tsconfig.json b/tsconfig.json
index 70ebc9f..689e10d 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -13,7 +13,7 @@
         "esModuleInterop": true,
         "forceConsistentCasingInFileNames": true,
         "lib": [
-            "es2015"
+            "es2019"
         ],
         "module": "commonjs",
         "moduleResolution": "node",