{"ast_node_type":"other","tokens":[{"end":89,"kind":"keyword","start":0,"text":"//"}]}
        // are not recorded. On the first `Success(..)`ful matcher, the spans are merged.
        // then the spans which became gated when parsing the unsuccessful matcher
        let mut gated_spans_snapshot = mem::take(&mut *psess.gated_spans.spans.borrow_mut());