{"ast_node_type":"other","tokens":[{"end":84,"kind":"keyword","start":0,"text":"//"}]}
                    // see: https://doc.rust-lang.org/std/fmt/#positional-parameters
                    // format args in the order they are specified.
                    if trimmed.chars().fold(true, |only_num, c| c.is_ascii_digit() && only_num) {