2 #![warn(clippy::unused_io_amount)]
6 fn question_mark<T: io::Read + io::Write>(s: &mut T) -> io::Result<()> {
8 let mut buf = [0u8; 4];
13 fn unwrap<T: io::Read + io::Write>(s: &mut T) {
14 s.write(b"test").unwrap();
15 let mut buf = [0u8; 4];
16 s.read(&mut buf).unwrap();