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Author: lcnr

compiler/rustc_type_ir/src/search_graph/mod.rs

@@ -130,6 +130,9 @@ impl PathKind {
     ///
     /// Given an inductive path `self` and a coinductive path `rest`,
     /// the path `self -> rest` would be coinductive.
+    ///
+    /// This operation represents an ordering and would be equivalent
+    /// to `max(self, rest)`.
     fn extend(self, rest: PathKind) -> PathKind {
         match (self, rest) {
             (PathKind::Coinductive, _) | (_, PathKind::Coinductive) => PathKind::Coinductive,