rust/src/libcore/macros.rs
2014-12-30 15:04:43 -08:00

99 lines
2.8 KiB
Rust

// Copyright 2014 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.
#![macro_escape]
/// Entry point of task panic, for details, see std::macros
#[macro_export]
macro_rules! panic {
() => (
panic!("explicit panic")
);
($msg:expr) => ({
static _MSG_FILE_LINE: (&'static str, &'static str, uint) = ($msg, file!(), line!());
::core::panicking::panic(&_MSG_FILE_LINE)
});
($fmt:expr, $($arg:tt)*) => ({
// The leading _'s are to avoid dead code warnings if this is
// used inside a dead function. Just `#[allow(dead_code)]` is
// insufficient, since the user may have
// `#[forbid(dead_code)]` and which cannot be overridden.
static _FILE_LINE: (&'static str, uint) = (file!(), line!());
::core::panicking::panic_fmt(format_args!($fmt, $($arg)*), &_FILE_LINE)
});
}
/// Runtime assertion, for details see std::macros
#[macro_export]
macro_rules! assert {
($cond:expr) => (
if !$cond {
panic!(concat!("assertion failed: ", stringify!($cond)))
}
);
($cond:expr, $($arg:tt)*) => (
if !$cond {
panic!($($arg)*)
}
);
}
/// Runtime assertion for equality, for details see std::macros
#[macro_export]
macro_rules! assert_eq {
($cond1:expr, $cond2:expr) => ({
let c1 = $cond1;
let c2 = $cond2;
if c1 != c2 || c2 != c1 {
panic!("expressions not equal, left: {}, right: {}", c1, c2);
}
})
}
/// Runtime assertion for equality, only without `--cfg ndebug`
#[macro_export]
macro_rules! debug_assert_eq {
($($a:tt)*) => ({
if cfg!(not(ndebug)) {
assert_eq!($($a)*);
}
})
}
/// Runtime assertion, disableable at compile time with `--cfg ndebug`
#[macro_export]
macro_rules! debug_assert {
($($arg:tt)*) => (if cfg!(not(ndebug)) { assert!($($arg)*); })
}
/// Short circuiting evaluation on Err
#[macro_export]
macro_rules! try {
($e:expr) => (match $e { Ok(e) => e, Err(e) => return Err(e) })
}
/// Writing a formatted string into a writer
#[macro_export]
macro_rules! write {
($dst:expr, $($arg:tt)*) => ((&mut *$dst).write_fmt(format_args!($($arg)*)))
}
/// Writing a formatted string plus a newline into a writer
#[macro_export]
macro_rules! writeln {
($dst:expr, $fmt:expr $($arg:tt)*) => (
write!($dst, concat!($fmt, "\n") $($arg)*)
)
}
#[macro_export]
macro_rules! unreachable { () => (panic!("unreachable code")) }