{"ast_node_type":"variable","tokens":[{"end":74,"kind":"keyword","start":0,"text":"let"}]}
    let input_expressions = mac_input.chunk_by(|tok| tok.kind() == T![,]);
    let mac_input = tt.syntax().children_with_tokens().skip(1).take_while(|it| *it != r_delim);
    let input_expressions = input_expressions