2 #![warn(clippy::unused_io_amount)]
4 use std::io::{self, Read};
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();
19 fn vectored<T: io::Read + io::Write>(s: &mut T) -> io::Result<()> {
20 s.read_vectored(&mut [io::IoSliceMut::new(&mut [])])?;
21 s.write_vectored(&[io::IoSlice::new(&[])])?;
25 fn ok(file: &str) -> Option<()> {
26 let mut reader = std::fs::File::open(file).ok()?;
27 let mut result = [0u8; 0];
28 reader.read(&mut result).ok()?;
32 #[allow(clippy::redundant_closure)]
33 #[allow(clippy::bind_instead_of_map)]
34 fn or_else(file: &str) -> io::Result<()> {
35 let mut reader = std::fs::File::open(file)?;
36 let mut result = [0u8; 0];
37 reader.read(&mut result).or_else(|err| Err(err))?;
46 fn or(file: &str) -> Result<(), Error> {
47 let mut reader = std::fs::File::open(file).unwrap();
48 let mut result = [0u8; 0];
49 reader.read(&mut result).or(Err(Error::Kind))?;
53 fn combine_or(file: &str) -> Result<(), Error> {
54 let mut reader = std::fs::File::open(file).unwrap();
55 let mut result = [0u8; 0];