7828c3dd28
https://github.com/rust-lang/rfcs/pull/221 The current terminology of "task failure" often causes problems when writing or speaking about code. You often want to talk about the possibility of an operation that returns a Result "failing", but cannot because of the ambiguity with task failure. Instead, you have to speak of "the failing case" or "when the operation does not succeed" or other circumlocutions. Likewise, we use a "Failure" header in rustdoc to describe when operations may fail the task, but it would often be helpful to separate out a section describing the "Err-producing" case. We have been steadily moving away from task failure and toward Result as an error-handling mechanism, so we should optimize our terminology accordingly: Result-producing functions should be easy to describe. To update your code, rename any call to `fail!` to `panic!` instead. Assuming you have not created your own macro named `panic!`, this will work on UNIX based systems: grep -lZR 'fail!' . | xargs -0 -l sed -i -e 's/fail!/panic!/g' You can of course also do this by hand. [breaking-change]
130 lines
3.6 KiB
Rust
130 lines
3.6 KiB
Rust
// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
|
|
// file at the top-level directory of this distribution and at
|
|
// http://rust-lang.org/COPYRIGHT.
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
|
|
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
|
|
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
|
|
// option. This file may not be copied, modified, or distributed
|
|
// except according to those terms.
|
|
|
|
//! Implementations of I/O traits for the IoResult type
|
|
//!
|
|
//! I/O constructors return option types to allow errors to be handled.
|
|
//! These implementations allow e.g. `IoResult<File>` to be used
|
|
//! as a `Reader` without unwrapping the result first.
|
|
|
|
use clone::Clone;
|
|
use result::{Ok, Err};
|
|
use super::{Reader, Writer, Listener, Acceptor, Seek, SeekStyle, IoResult};
|
|
|
|
impl<W: Writer> Writer for IoResult<W> {
|
|
fn write(&mut self, buf: &[u8]) -> IoResult<()> {
|
|
match *self {
|
|
Ok(ref mut writer) => writer.write(buf),
|
|
Err(ref e) => Err((*e).clone())
|
|
}
|
|
}
|
|
|
|
fn flush(&mut self) -> IoResult<()> {
|
|
match *self {
|
|
Ok(ref mut writer) => writer.flush(),
|
|
Err(ref e) => Err(e.clone()),
|
|
}
|
|
}
|
|
}
|
|
|
|
impl<R: Reader> Reader for IoResult<R> {
|
|
fn read(&mut self, buf: &mut [u8]) -> IoResult<uint> {
|
|
match *self {
|
|
Ok(ref mut reader) => reader.read(buf),
|
|
Err(ref e) => Err(e.clone()),
|
|
}
|
|
}
|
|
}
|
|
|
|
impl<S: Seek> Seek for IoResult<S> {
|
|
fn tell(&self) -> IoResult<u64> {
|
|
match *self {
|
|
Ok(ref seeker) => seeker.tell(),
|
|
Err(ref e) => Err(e.clone()),
|
|
}
|
|
}
|
|
fn seek(&mut self, pos: i64, style: SeekStyle) -> IoResult<()> {
|
|
match *self {
|
|
Ok(ref mut seeker) => seeker.seek(pos, style),
|
|
Err(ref e) => Err(e.clone())
|
|
}
|
|
}
|
|
}
|
|
|
|
impl<T, A: Acceptor<T>, L: Listener<T, A>> Listener<T, A> for IoResult<L> {
|
|
fn listen(self) -> IoResult<A> {
|
|
match self {
|
|
Ok(listener) => listener.listen(),
|
|
Err(e) => Err(e),
|
|
}
|
|
}
|
|
}
|
|
|
|
impl<T, A: Acceptor<T>> Acceptor<T> for IoResult<A> {
|
|
fn accept(&mut self) -> IoResult<T> {
|
|
match *self {
|
|
Ok(ref mut acceptor) => acceptor.accept(),
|
|
Err(ref e) => Err(e.clone()),
|
|
}
|
|
}
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod test {
|
|
use prelude::*;
|
|
use super::super::mem::*;
|
|
use io;
|
|
|
|
#[test]
|
|
fn test_option_writer() {
|
|
let mut writer: io::IoResult<MemWriter> = Ok(MemWriter::new());
|
|
writer.write([0, 1, 2]).unwrap();
|
|
writer.flush().unwrap();
|
|
assert_eq!(writer.unwrap().unwrap(), vec!(0, 1, 2));
|
|
}
|
|
|
|
#[test]
|
|
fn test_option_writer_error() {
|
|
let mut writer: io::IoResult<MemWriter> =
|
|
Err(io::standard_error(io::EndOfFile));
|
|
|
|
match writer.write([0, 0, 0]) {
|
|
Ok(..) => panic!(),
|
|
Err(e) => assert_eq!(e.kind, io::EndOfFile),
|
|
}
|
|
match writer.flush() {
|
|
Ok(..) => panic!(),
|
|
Err(e) => assert_eq!(e.kind, io::EndOfFile),
|
|
}
|
|
}
|
|
|
|
#[test]
|
|
fn test_option_reader() {
|
|
let mut reader: io::IoResult<MemReader> =
|
|
Ok(MemReader::new(vec!(0, 1, 2, 3)));
|
|
let mut buf = [0, 0];
|
|
reader.read(buf).unwrap();
|
|
let b: &[_] = &[0, 1];
|
|
assert_eq!(buf.as_slice(), b);
|
|
}
|
|
|
|
#[test]
|
|
fn test_option_reader_error() {
|
|
let mut reader: io::IoResult<MemReader> =
|
|
Err(io::standard_error(io::EndOfFile));
|
|
let mut buf = [];
|
|
|
|
match reader.read(buf) {
|
|
Ok(..) => panic!(),
|
|
Err(e) => assert_eq!(e.kind, io::EndOfFile),
|
|
}
|
|
}
|
|
}
|