{"ast_node_type":"variable","tokens":[{"end":95,"kind":"keyword","start":0,"text":"let"}]}
        let orig_parent_def = mem::replace(&mut self.invocation_parent.parent_def, parent_def);
    fn with_parent<F: FnOnce(&mut Self)>(&mut self, parent_def: LocalDefId, f: F) {
        f(self);