'outer: loop {

    loop {

        loop {

        let done = loop {

                Ok(None) => break 'outer,

                Ok(None) => break true,

                    break;

                    break false;

        };
        if done {
            std::fs::rename(&path_, &path_.with_extension("change"))?;
            break;

        std::fs::rename(&path_, &path_.with_extension("change"))?;