pub(crate) fn load_exec(&mut self, path: &Path, allow_repeat: bool) -> Result<bool, RubyError> {
        let absolute_path = match path.canonicalize() {
            Ok(path) => path,
            Err(ioerr) => {
                let msg = format!("File not found. {:?}\n{}", path, ioerr);
                return Err(RubyError::runtime(msg));
            }
        };
        let res = self.globals.add_source_file(&absolute_path);
        if !allow_repeat && res.is_none() {
            return Ok(false);
        }
        let program = self.load_file(&absolute_path)?;
        self.run(absolute_path, program)?;
        Ok(true)
    }
Load file and execute.
returns Ok(true) if the file was actually loaded and executed.
otherwise, returns Ok(false).
ruruby/src/vm/executor/loader.rs