{"ast_node_type":"variable","tokens":[{"end":44,"kind":"keyword","start":0,"text":"let"}]}
        let invoc_id = self.visit_invoc(id);
    fn visit_invoc_in_module(&mut self, id: NodeId) -> MacroRulesScopeRef<'ra> {
        self.parent_scope.module.unexpanded_invocations.borrow_mut().insert(invoc_id);