{"ast_node_type":"other","tokens":[{"end":87,"kind":"keyword","start":0,"text":"for"}]}
    for idx in (0..working.len()).filter(|idx| working[*idx..].starts_with(&end_pat)) {
    let mut found = None;
        let (eol_txt, rest) = parse_to_newline(&working[(idx + end_pat.len())..]);