{"ast_node_type":"other","tokens":[{"end":77,"kind":"keyword","start":0,"text":"//"}]}
            //    `ExpectHasType(expected_ty)`, or the `formal_ty` otherwise.
            //    to, which is `expected_ty` if `rvalue_hint` returns an
            let coerced_ty = expectation.only_has_type(self).unwrap_or(formal_input_ty);