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// Copyright (c) 2017 Baidu, Inc. All Rights Reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in
// the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Baidu, Inc., nor the names of its
// contributors may be used to endorse or promote products derived
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//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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//! Standard library macros
//!
//! This modules contains a set of macros which are exported from the standard
//! library. Each macro is available for use when linking against the standard
//! library.
/// The entry point for panic of Rust threads.
///
/// This macro is used to inject panic into a Rust thread, causing the thread to
/// panic entirely. Each thread's panic can be reaped as the `Box<Any>` type,
/// and the single-argument form of the `panic!` macro will be the value which
/// is transmitted.
///
/// The multi-argument form of this macro panics with a string and has the
/// `format!` syntax for building a string.
///
/// # Current implementation
///
/// If the main thread panics it will terminate all your threads and end your
/// program with code `101`.
///
#[macro_export]
#[allow_internal_unstable]
macro_rules! panic {
() => ({
panic!("explicit panic")
});
($msg:expr) => ({
$crate::rt::begin_panic($msg, &(file!(), line!(), column!()))
});
($fmt:expr, $($arg:tt)+) => ({
$crate::rt::begin_panic_fmt(&format_args!($fmt, $($arg)+),
&(file!(), line!(), column!()))
});
}
/// Macro for printing to the standard output.
///
/// Equivalent to the `println!` macro except that a newline is not printed at
/// the end of the message.
///
/// Note that stdout is frequently line-buffered by default so it may be
/// necessary to use `io::stdout().flush()` to ensure the output is emitted
/// immediately.
///
/// Use `print!` only for the primary output of your program. Use
/// `eprint!` instead to print error and progress messages.
///
/// # Panics
///
/// Panics if writing to `io::stdout()` fails.
#[cfg(feature = "stdio")]
#[macro_export]
#[allow_internal_unstable]
macro_rules! print {
($($arg:tt)*) => ($crate::io::_print(format_args!($($arg)*)));
}
/// Macro for printing to the standard output, with a newline. On all
/// platforms, the newline is the LINE FEED character (`\n`/`U+000A`) alone
/// (no additional CARRIAGE RETURN (`\r`/`U+000D`).
///
/// Use the `format!` syntax to write data to the standard output.
/// See `std::fmt` for more information.
///
/// Use `println!` only for the primary output of your program. Use
/// `eprintln!` instead to print error and progress messages.
///
/// # Panics
///
/// Panics if writing to `io::stdout` fails.
#[cfg(feature = "stdio")]
#[macro_export]
macro_rules! println {
() => (print!("\n"));
($fmt:expr) => (print!(concat!($fmt, "\n")));
($fmt:expr, $($arg:tt)*) => (print!(concat!($fmt, "\n"), $($arg)*));
}
#[cfg(not(feature = "stdio"))]
#[macro_export]
macro_rules! print { ($($arg:tt)*) => ({}) }
#[cfg(not(feature = "stdio"))]
#[macro_export]
macro_rules! println { ($($arg:tt)*) => ({}) }
/// Macro for printing to the standard error.
///
/// Equivalent to the `print!` macro, except that output goes to
/// `io::stderr` instead of `io::stdout`. See `print!` for
/// example usage.
///
/// Use `eprint!` only for error and progress messages. Use `print!`
/// instead for the primary output of your program.
///
/// # Panics
///
/// Panics if writing to `io::stderr` fails.
#[cfg(feature = "stdio")]
#[macro_export]
#[allow_internal_unstable]
macro_rules! eprint {
($($arg:tt)*) => ($crate::io::_eprint(format_args!($($arg)*)));
}
/// Macro for printing to the standard error, with a newline.
///
/// Equivalent to the `println!` macro, except that output goes to
/// `io::stderr` instead of `io::stdout`. See `println!` for
/// example usage.
///
/// Use `eprintln!` only for error and progress messages. Use `println!`
/// instead for the primary output of your program.
///
/// # Panics
///
/// Panics if writing to `io::stderr` fails.
#[cfg(feature = "stdio")]
#[macro_export]
macro_rules! eprintln {
() => (eprint!("\n"));
($fmt:expr) => (eprint!(concat!($fmt, "\n")));
($fmt:expr, $($arg:tt)*) => (eprint!(concat!($fmt, "\n"), $($arg)*));
}
#[cfg(not(feature = "stdio"))]
#[macro_export]
macro_rules! eprint { ($($arg:tt)*) => ({}) }
#[cfg(not(feature = "stdio"))]
#[macro_export]
macro_rules! eprintln { ($($arg:tt)*) => ({}) }