fn main() {

}

impl<'a> FileResp {
	fn into_download_param(&self, fp: &FileParam<'a>) -> DownloadParam<'a> {
		DownloadParam {
			foo: &self.foo,
			bar: fp.bar,
		}
	}
}

struct DownloadParam<'a> {
	foo: &'a str,
	bar: &'a str,
}

struct FileResp {
	foo: String,
}

struct FileParam<'a> {
    bar: &'a str,
}