{"ast_node_type":"variable","tokens":[{"end":99,"kind":"keyword","start":0,"text":"let"}]}
        let old_parent_scope = self.r.invocation_parent_scopes.insert(invoc_id, self.parent_scope);
        let invoc_id = id.placeholder_to_expn_id();
        assert!(old_parent_scope.is_none(), "invocation data is reset for an invocation");