Allow specifying TReturn and TNext for AsyncIterableIterator and AsyncIterable

Author: bterlson

src/lib/es2018.asynciterable.d.ts

@@ -16,10 +16,10 @@ interface AsyncIterator<T, TReturn = any, TNext = undefined> {
     throw?(e?: any): Promise<IteratorResult<T, TReturn>>;
 }
 
-interface AsyncIterable<T> {
-    [Symbol.asyncIterator](): AsyncIterator<T>;
+interface AsyncIterable<T, TReturn = any, TNext = undefined> {
+    [Symbol.asyncIterator](): AsyncIterator<T, TReturn, TNext>;
 }
 
-interface AsyncIterableIterator<T> extends AsyncIterator<T> {
-    [Symbol.asyncIterator](): AsyncIterableIterator<T>;
-}
+interface AsyncIterableIterator<T, TReturn = any, TNext = undefined> extends AsyncIterator<T, TReturn, TNext> {
+    [Symbol.asyncIterator](): AsyncIterableIterator<T, TReturn, TNext>;
+}