{"ast_node_type":"other","tokens":[{"end":87,"kind":"keyword","start":0,"text":"self.used_mentioned_items.insert(MentionedItem::Fn(fn_ty));"}]}
                            self.used_mentioned_items.insert(MentionedItem::Fn(fn_ty));
                            // *Before* monomorphizing, record that we already handled this mention.
                            let fn_ty = self.monomorphize(fn_ty);