{"ast_node_type":"function","tokens":[{"end":71,"kind":"keyword","start":0,"text":"//"}]}
                    //     async fn foo(_: std::cell::Ref<u32>) { ... }
                    //     impl Foo for std::cell::Ref<u32> // note lack of '_
                    LifetimeRibKind::AnonymousCreateParameter { report_in_path: true, .. }