Use $crate and macro reexport to reduce duplicated code

Many of libstd's macros are now re-exported from libcore and libcollections.
Their libstd definitions have moved to a macros_stage0 module and can disappear
after the next snapshot.

Where the two crates had already diverged, I took the libstd versions as
they're generally newer and better-tested. See e.g. d3c831b, which was a fix to
libstd's assert_eq!() that didn't make it into libcore's.

Fixes #16806.
This commit is contained in:
Keegan McAllister 2014-09-15 19:29:47 -07:00
parent 1c2fddc6bf
commit 73806ddd0f
13 changed files with 915 additions and 246 deletions

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@ -51,6 +51,9 @@ pub use string::String;
pub use vec::Vec;
pub use vec_map::VecMap;
// Needed for the vec! macro
pub use alloc::boxed;
mod macros;
pub mod binary_heap;

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@ -11,6 +11,8 @@
#![macro_escape]
/// Creates a `std::vec::Vec` containing the arguments.
// NOTE: remove after the next snapshot
#[cfg(stage0)]
macro_rules! vec {
($($e:expr),*) => ({
// leading _ to allow empty construction without a warning.
@ -21,3 +23,13 @@ macro_rules! vec {
($($e:expr),+,) => (vec!($($e),+))
}
/// Creates a `Vec` containing the arguments.
#[cfg(not(stage0))]
#[macro_export]
macro_rules! vec {
($($x:expr),*) => ({
let xs: $crate::boxed::Box<[_]> = box [$($x),*];
$crate::slice::SliceExt::into_vec(xs)
});
($($x:expr,)*) => (vec![$($x),*])
}

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@ -20,12 +20,15 @@ use mem;
use option::Option;
use option::Option::{Some, None};
use ops::{Deref, FnOnce};
use result::Result::{Ok, Err};
use result::Result::Ok;
use result;
use slice::SliceExt;
use slice;
use str::{self, StrExt, Utf8Error};
// NOTE: for old macros; remove after the next snapshot
#[cfg(stage0)] use result::Result::Err;
pub use self::num::radix;
pub use self::num::Radix;
pub use self::num::RadixFmt;

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@ -130,6 +130,7 @@ mod array;
#[doc(hidden)]
mod core {
pub use panicking;
pub use fmt;
}
#[doc(hidden)]

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@ -30,7 +30,26 @@ macro_rules! panic {
});
}
/// Runtime assertion, for details see std::macros
/// Ensure that a boolean expression is `true` at runtime.
///
/// This will invoke the `panic!` macro if the provided expression cannot be
/// evaluated to `true` at runtime.
///
/// # Example
///
/// ```
/// // the panic message for these assertions is the stringified value of the
/// // expression given.
/// assert!(true);
/// # fn some_computation() -> bool { true }
/// assert!(some_computation());
///
/// // assert with a custom message
/// # let x = true;
/// assert!(x, "x wasn't true!");
/// # let a = 3i; let b = 27i;
/// assert!(a + b == 30, "a = {}, b = {}", a, b);
/// ```
#[macro_export]
macro_rules! assert {
($cond:expr) => (
@ -38,61 +57,197 @@ macro_rules! assert {
panic!(concat!("assertion failed: ", stringify!($cond)))
}
);
($cond:expr, $($arg:tt)*) => (
($cond:expr, $($arg:expr),+) => (
if !$cond {
panic!($($arg)*)
panic!($($arg),+)
}
);
}
/// Runtime assertion for equality, for details see std::macros
/// Asserts that two expressions are equal to each other, testing equality in
/// both directions.
///
/// On panic, this macro will print the values of the expressions.
///
/// # Example
///
/// ```
/// let a = 3i;
/// let b = 1i + 2i;
/// assert_eq!(a, b);
/// ```
#[macro_export]
macro_rules! assert_eq {
($cond1:expr, $cond2:expr) => ({
let c1 = $cond1;
let c2 = $cond2;
if c1 != c2 || c2 != c1 {
panic!("expressions not equal, left: {}, right: {}", c1, c2);
($left:expr , $right:expr) => ({
match (&($left), &($right)) {
(left_val, right_val) => {
// check both directions of equality....
if !((*left_val == *right_val) &&
(*right_val == *left_val)) {
panic!("assertion failed: `(left == right) && (right == left)` \
(left: `{}`, right: `{}`)", *left_val, *right_val)
}
}
}
})
}
/// Runtime assertion for equality, only without `--cfg ndebug`
#[macro_export]
macro_rules! debug_assert_eq {
($($a:tt)*) => ({
if cfg!(not(ndebug)) {
assert_eq!($($a)*);
}
})
}
/// Runtime assertion, disableable at compile time with `--cfg ndebug`
/// Ensure that a boolean expression is `true` at runtime.
///
/// This will invoke the `panic!` macro if the provided expression cannot be
/// evaluated to `true` at runtime.
///
/// Unlike `assert!`, `debug_assert!` statements can be disabled by passing
/// `--cfg ndebug` to the compiler. This makes `debug_assert!` useful for
/// checks that are too expensive to be present in a release build but may be
/// helpful during development.
///
/// # Example
///
/// ```
/// // the panic message for these assertions is the stringified value of the
/// // expression given.
/// debug_assert!(true);
/// # fn some_expensive_computation() -> bool { true }
/// debug_assert!(some_expensive_computation());
///
/// // assert with a custom message
/// # let x = true;
/// debug_assert!(x, "x wasn't true!");
/// # let a = 3i; let b = 27i;
/// debug_assert!(a + b == 30, "a = {}, b = {}", a, b);
/// ```
#[macro_export]
macro_rules! debug_assert {
($($arg:tt)*) => (if cfg!(not(ndebug)) { assert!($($arg)*); })
}
/// Short circuiting evaluation on Err
/// Asserts that two expressions are equal to each other, testing equality in
/// both directions.
///
/// On panic, this macro will print the values of the expressions.
///
/// Unlike `assert_eq!`, `debug_assert_eq!` statements can be disabled by
/// passing `--cfg ndebug` to the compiler. This makes `debug_assert_eq!`
/// useful for checks that are too expensive to be present in a release build
/// but may be helpful during development.
///
/// # Example
///
/// ```
/// let a = 3i;
/// let b = 1i + 2i;
/// debug_assert_eq!(a, b);
/// ```
#[macro_export]
macro_rules! debug_assert_eq {
($($arg:tt)*) => (if cfg!(not(ndebug)) { assert_eq!($($arg)*); })
}
#[cfg(stage0)]
#[macro_export]
macro_rules! try {
($e:expr) => (match $e { Ok(e) => e, Err(e) => return Err(e) })
}
/// Writing a formatted string into a writer
/// Short circuiting evaluation on Err
///
/// `libstd` contains a more general `try!` macro that uses `FromError`.
#[cfg(not(stage0))]
#[macro_export]
macro_rules! try {
($e:expr) => ({
use $crate::result::Result::{Ok, Err};
match $e {
Ok(e) => e,
Err(e) => return Err(e),
}
})
}
/// Use the `format!` syntax to write data into a buffer of type `&mut Writer`.
/// See `std::fmt` for more information.
///
/// # Example
///
/// ```
/// # #![allow(unused_must_use)]
///
/// let mut w = Vec::new();
/// write!(&mut w, "test");
/// write!(&mut w, "formatted {}", "arguments");
/// ```
#[macro_export]
macro_rules! write {
($dst:expr, $($arg:tt)*) => ((&mut *$dst).write_fmt(format_args!($($arg)*)))
}
/// Writing a formatted string plus a newline into a writer
/// Equivalent to the `write!` macro, except that a newline is appended after
/// the message is written.
#[macro_export]
#[stable]
macro_rules! writeln {
($dst:expr, $fmt:expr $($arg:tt)*) => (
write!($dst, concat!($fmt, "\n") $($arg)*)
)
}
/// A utility macro for indicating unreachable code.
///
/// This is useful any time that the compiler can't determine that some code is unreachable. For
/// example:
///
/// * Match arms with guard conditions.
/// * Loops that dynamically terminate.
/// * Iterators that dynamically terminate.
///
/// # Panics
///
/// This will always panic.
///
/// # Examples
///
/// Match arms:
///
/// ```rust
/// fn foo(x: Option<int>) {
/// match x {
/// Some(n) if n >= 0 => println!("Some(Non-negative)"),
/// Some(n) if n < 0 => println!("Some(Negative)"),
/// Some(_) => unreachable!(), // compile error if commented out
/// None => println!("None")
/// }
/// }
/// ```
///
/// Iterators:
///
/// ```rust
/// fn divide_by_three(x: u32) -> u32 { // one of the poorest implementations of x/3
/// for i in std::iter::count(0_u32, 1) {
/// if 3*i < i { panic!("u32 overflow"); }
/// if x < 3*i { return i-1; }
/// }
/// unreachable!();
/// }
/// ```
#[macro_export]
macro_rules! unreachable { () => (panic!("unreachable code")) }
macro_rules! unreachable {
() => ({
panic!("internal error: entered unreachable code")
});
($msg:expr) => ({
unreachable!("{}", $msg)
});
($fmt:expr, $($arg:tt)*) => ({
panic!(concat!("internal error: entered unreachable code: ", $fmt), $($arg)*)
});
}
/// A standardised placeholder for marking unfinished code. It panics with the
/// message `"not yet implemented"` when executed.
#[macro_export]
macro_rules! unimplemented {
() => (panic!("not yet implemented"))
}

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@ -21,7 +21,9 @@ use hash::{Hash, Hasher, RandomSipHasher};
use iter::{Iterator, IteratorExt, IteratorCloneExt, FromIterator, Map, Chain, Extend};
use ops::{BitOr, BitAnd, BitXor, Sub};
use option::Option::{Some, None, self};
use result::Result::{Ok, Err};
// NOTE: for old macros; remove after the next snapshot
#[cfg(stage0)] use result::Result::{Ok, Err};
use super::map::{self, HashMap, Keys, INITIAL_CAPACITY};

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@ -18,11 +18,14 @@ use iter::ExactSizeIterator;
use ops::Drop;
use option::Option;
use option::Option::{Some, None};
use result::Result::{Ok, Err};
use result::Result::Ok;
use slice::{SliceExt};
use slice;
use vec::Vec;
// NOTE: for old macros; remove after the next snapshot
#[cfg(stage0)] use result::Result::Err;
/// Wraps a Reader and buffers input from it
///
/// It can be excessively inefficient to work directly with a `Reader`. For

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@ -117,13 +117,18 @@
#![reexport_test_harness_main = "test_main"]
#![macro_reexport(assert, assert_eq, debug_assert, debug_assert_eq,
unreachable, unimplemented, write, writeln, vec)]
#[cfg(test)] #[phase(plugin, link)] extern crate log;
extern crate alloc;
extern crate unicode;
#[phase(plugin, link)]
extern crate core;
#[phase(plugin, link)]
extern crate "collections" as core_collections;
extern crate "rand" as core_rand;
extern crate alloc;
extern crate unicode;
extern crate libc;
// Make std testable by not duplicating lang items. See #2912
@ -167,7 +172,8 @@ pub use unicode::char;
/* Exported macros */
pub mod macros;
#[cfg(stage0)] pub mod macros_stage0;
#[cfg(not(stage0))] pub mod macros;
pub mod bitflags;
mod rtdeps;

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@ -57,179 +57,6 @@ macro_rules! panic {
});
}
/// Ensure that a boolean expression is `true` at runtime.
///
/// This will invoke the `panic!` macro if the provided expression cannot be
/// evaluated to `true` at runtime.
///
/// # Example
///
/// ```
/// // the panic message for these assertions is the stringified value of the
/// // expression given.
/// assert!(true);
/// # fn some_computation() -> bool { true }
/// assert!(some_computation());
///
/// // assert with a custom message
/// # let x = true;
/// assert!(x, "x wasn't true!");
/// # let a = 3i; let b = 27i;
/// assert!(a + b == 30, "a = {}, b = {}", a, b);
/// ```
#[macro_export]
macro_rules! assert {
($cond:expr) => (
if !$cond {
panic!(concat!("assertion failed: ", stringify!($cond)))
}
);
($cond:expr, $($arg:expr),+) => (
if !$cond {
panic!($($arg),+)
}
);
}
/// Asserts that two expressions are equal to each other, testing equality in
/// both directions.
///
/// On panic, this macro will print the values of the expressions.
///
/// # Example
///
/// ```
/// let a = 3i;
/// let b = 1i + 2i;
/// assert_eq!(a, b);
/// ```
#[macro_export]
macro_rules! assert_eq {
($left:expr , $right:expr) => ({
match (&($left), &($right)) {
(left_val, right_val) => {
// check both directions of equality....
if !((*left_val == *right_val) &&
(*right_val == *left_val)) {
panic!("assertion failed: `(left == right) && (right == left)` \
(left: `{}`, right: `{}`)", *left_val, *right_val)
}
}
}
})
}
/// Ensure that a boolean expression is `true` at runtime.
///
/// This will invoke the `panic!` macro if the provided expression cannot be
/// evaluated to `true` at runtime.
///
/// Unlike `assert!`, `debug_assert!` statements can be disabled by passing
/// `--cfg ndebug` to the compiler. This makes `debug_assert!` useful for
/// checks that are too expensive to be present in a release build but may be
/// helpful during development.
///
/// # Example
///
/// ```
/// // the panic message for these assertions is the stringified value of the
/// // expression given.
/// debug_assert!(true);
/// # fn some_expensive_computation() -> bool { true }
/// debug_assert!(some_expensive_computation());
///
/// // assert with a custom message
/// # let x = true;
/// debug_assert!(x, "x wasn't true!");
/// # let a = 3i; let b = 27i;
/// debug_assert!(a + b == 30, "a = {}, b = {}", a, b);
/// ```
#[macro_export]
macro_rules! debug_assert {
($($arg:tt)*) => (if cfg!(not(ndebug)) { assert!($($arg)*); })
}
/// Asserts that two expressions are equal to each other, testing equality in
/// both directions.
///
/// On panic, this macro will print the values of the expressions.
///
/// Unlike `assert_eq!`, `debug_assert_eq!` statements can be disabled by
/// passing `--cfg ndebug` to the compiler. This makes `debug_assert_eq!`
/// useful for checks that are too expensive to be present in a release build
/// but may be helpful during development.
///
/// # Example
///
/// ```
/// let a = 3i;
/// let b = 1i + 2i;
/// debug_assert_eq!(a, b);
/// ```
#[macro_export]
macro_rules! debug_assert_eq {
($($arg:tt)*) => (if cfg!(not(ndebug)) { assert_eq!($($arg)*); })
}
/// A utility macro for indicating unreachable code.
///
/// This is useful any time that the compiler can't determine that some code is unreachable. For
/// example:
///
/// * Match arms with guard conditions.
/// * Loops that dynamically terminate.
/// * Iterators that dynamically terminate.
///
/// # Panics
///
/// This will always panic.
///
/// # Examples
///
/// Match arms:
///
/// ```rust
/// fn foo(x: Option<int>) {
/// match x {
/// Some(n) if n >= 0 => println!("Some(Non-negative)"),
/// Some(n) if n < 0 => println!("Some(Negative)"),
/// Some(_) => unreachable!(), // compile error if commented out
/// None => println!("None")
/// }
/// }
/// ```
///
/// Iterators:
///
/// ```rust
/// fn divide_by_three(x: u32) -> u32 { // one of the poorest implementations of x/3
/// for i in std::iter::count(0_u32, 1) {
/// if 3*i < i { panic!("u32 overflow"); }
/// if x < 3*i { return i-1; }
/// }
/// unreachable!();
/// }
/// ```
#[macro_export]
macro_rules! unreachable {
() => ({
panic!("internal error: entered unreachable code")
});
($msg:expr) => ({
unreachable!("{}", $msg)
});
($fmt:expr, $($arg:tt)*) => ({
panic!(concat!("internal error: entered unreachable code: ", $fmt), $($arg)*)
});
}
/// A standardised placeholder for marking unfinished code. It panics with the
/// message `"not yet implemented"` when executed.
#[macro_export]
macro_rules! unimplemented {
() => (panic!("not yet implemented"))
}
/// Use the syntax described in `std::fmt` to create a value of type `String`.
/// See `std::fmt` for more information.
///
@ -246,34 +73,6 @@ macro_rules! format {
($($arg:tt)*) => (::std::fmt::format(format_args!($($arg)*)))
}
/// Use the `format!` syntax to write data into a buffer of type `&mut Writer`.
/// See `std::fmt` for more information.
///
/// # Example
///
/// ```
/// # #![allow(unused_must_use)]
///
/// let mut w = Vec::new();
/// write!(&mut w, "test");
/// write!(&mut w, "formatted {}", "arguments");
/// ```
#[macro_export]
#[stable]
macro_rules! write {
($dst:expr, $($arg:tt)*) => ((&mut *$dst).write_fmt(format_args!($($arg)*)))
}
/// Equivalent to the `write!` macro, except that a newline is appended after
/// the message is written.
#[macro_export]
#[stable]
macro_rules! writeln {
($dst:expr, $fmt:expr $($arg:tt)*) => (
write!($dst, concat!($fmt, "\n") $($arg)*)
)
}
/// Equivalent to the `println!` macro except that a newline is not printed at
/// the end of the message.
#[macro_export]
@ -306,23 +105,15 @@ macro_rules! println {
#[macro_export]
macro_rules! try {
($expr:expr) => ({
use $crate::result::Result::{Ok, Err};
match $expr {
Ok(val) => val,
Err(err) => return Err(::std::error::FromError::from_error(err))
Err(err) => return Err($crate::error::FromError::from_error(err)),
}
})
}
/// Create a `std::vec::Vec` containing the arguments.
#[macro_export]
macro_rules! vec {
($($x:expr),*) => ({
let xs: ::std::boxed::Box<[_]> = box [$($x),*];
::std::slice::SliceExt::into_vec(xs)
});
($($x:expr,)*) => (vec![$($x),*])
}
/// A macro to select an event from a number of receivers.
///
/// This macro is used to wait for the first event to occur on a number of
@ -358,7 +149,7 @@ macro_rules! select {
(
$($name:pat = $rx:ident.$meth:ident() => $code:expr),+
) => ({
use std::sync::mpsc::Select;
use $crate::sync::mpsc::Select;
let sel = Select::new();
$( let mut $rx = sel.handle(&$rx); )+
unsafe {

649
src/libstd/macros_stage0.rs Normal file
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@ -0,0 +1,649 @@
// 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.
//! 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.
#![experimental]
#![macro_escape]
/// The entry point for panic of Rust tasks.
///
/// This macro is used to inject panic into a Rust task, causing the task to
/// unwind and panic entirely. Each task'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.
///
/// # Example
///
/// ```should_fail
/// # #![allow(unreachable_code)]
/// panic!();
/// panic!("this is a terrible mistake!");
/// panic!(4i); // panic with the value of 4 to be collected elsewhere
/// panic!("this is a {} {message}", "fancy", message = "message");
/// ```
#[macro_export]
macro_rules! panic {
() => ({
panic!("explicit panic")
});
($msg:expr) => ({
// static requires less code at runtime, more constant data
static _FILE_LINE: (&'static str, uint) = (file!(), line!());
::std::rt::begin_unwind($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!());
::std::rt::begin_unwind_fmt(format_args!($fmt, $($arg)*), &_FILE_LINE)
});
}
/// Ensure that a boolean expression is `true` at runtime.
///
/// This will invoke the `panic!` macro if the provided expression cannot be
/// evaluated to `true` at runtime.
///
/// # Example
///
/// ```
/// // the panic message for these assertions is the stringified value of the
/// // expression given.
/// assert!(true);
/// # fn some_computation() -> bool { true }
/// assert!(some_computation());
///
/// // assert with a custom message
/// # let x = true;
/// assert!(x, "x wasn't true!");
/// # let a = 3i; let b = 27i;
/// assert!(a + b == 30, "a = {}, b = {}", a, b);
/// ```
#[macro_export]
macro_rules! assert {
($cond:expr) => (
if !$cond {
panic!(concat!("assertion failed: ", stringify!($cond)))
}
);
($cond:expr, $($arg:expr),+) => (
if !$cond {
panic!($($arg),+)
}
);
}
/// Asserts that two expressions are equal to each other, testing equality in
/// both directions.
///
/// On panic, this macro will print the values of the expressions.
///
/// # Example
///
/// ```
/// let a = 3i;
/// let b = 1i + 2i;
/// assert_eq!(a, b);
/// ```
#[macro_export]
macro_rules! assert_eq {
($left:expr , $right:expr) => ({
match (&($left), &($right)) {
(left_val, right_val) => {
// check both directions of equality....
if !((*left_val == *right_val) &&
(*right_val == *left_val)) {
panic!("assertion failed: `(left == right) && (right == left)` \
(left: `{}`, right: `{}`)", *left_val, *right_val)
}
}
}
})
}
/// Ensure that a boolean expression is `true` at runtime.
///
/// This will invoke the `panic!` macro if the provided expression cannot be
/// evaluated to `true` at runtime.
///
/// Unlike `assert!`, `debug_assert!` statements can be disabled by passing
/// `--cfg ndebug` to the compiler. This makes `debug_assert!` useful for
/// checks that are too expensive to be present in a release build but may be
/// helpful during development.
///
/// # Example
///
/// ```
/// // the panic message for these assertions is the stringified value of the
/// // expression given.
/// debug_assert!(true);
/// # fn some_expensive_computation() -> bool { true }
/// debug_assert!(some_expensive_computation());
///
/// // assert with a custom message
/// # let x = true;
/// debug_assert!(x, "x wasn't true!");
/// # let a = 3i; let b = 27i;
/// debug_assert!(a + b == 30, "a = {}, b = {}", a, b);
/// ```
#[macro_export]
macro_rules! debug_assert {
($($arg:tt)*) => (if cfg!(not(ndebug)) { assert!($($arg)*); })
}
/// Asserts that two expressions are equal to each other, testing equality in
/// both directions.
///
/// On panic, this macro will print the values of the expressions.
///
/// Unlike `assert_eq!`, `debug_assert_eq!` statements can be disabled by
/// passing `--cfg ndebug` to the compiler. This makes `debug_assert_eq!`
/// useful for checks that are too expensive to be present in a release build
/// but may be helpful during development.
///
/// # Example
///
/// ```
/// let a = 3i;
/// let b = 1i + 2i;
/// debug_assert_eq!(a, b);
/// ```
#[macro_export]
macro_rules! debug_assert_eq {
($($arg:tt)*) => (if cfg!(not(ndebug)) { assert_eq!($($arg)*); })
}
/// A utility macro for indicating unreachable code.
///
/// This is useful any time that the compiler can't determine that some code is unreachable. For
/// example:
///
/// * Match arms with guard conditions.
/// * Loops that dynamically terminate.
/// * Iterators that dynamically terminate.
///
/// # Panics
///
/// This will always panic.
///
/// # Examples
///
/// Match arms:
///
/// ```rust
/// fn foo(x: Option<int>) {
/// match x {
/// Some(n) if n >= 0 => println!("Some(Non-negative)"),
/// Some(n) if n < 0 => println!("Some(Negative)"),
/// Some(_) => unreachable!(), // compile error if commented out
/// None => println!("None")
/// }
/// }
/// ```
///
/// Iterators:
///
/// ```rust
/// fn divide_by_three(x: u32) -> u32 { // one of the poorest implementations of x/3
/// for i in std::iter::count(0_u32, 1) {
/// if 3*i < i { panic!("u32 overflow"); }
/// if x < 3*i { return i-1; }
/// }
/// unreachable!();
/// }
/// ```
#[macro_export]
macro_rules! unreachable {
() => ({
panic!("internal error: entered unreachable code")
});
($msg:expr) => ({
unreachable!("{}", $msg)
});
($fmt:expr, $($arg:tt)*) => ({
panic!(concat!("internal error: entered unreachable code: ", $fmt), $($arg)*)
});
}
/// A standardised placeholder for marking unfinished code. It panics with the
/// message `"not yet implemented"` when executed.
#[macro_export]
macro_rules! unimplemented {
() => (panic!("not yet implemented"))
}
/// Use the syntax described in `std::fmt` to create a value of type `String`.
/// See `std::fmt` for more information.
///
/// # Example
///
/// ```
/// format!("test");
/// format!("hello {}", "world!");
/// format!("x = {}, y = {y}", 10i, y = 30i);
/// ```
#[macro_export]
#[stable]
macro_rules! format {
($($arg:tt)*) => (::std::fmt::format(format_args!($($arg)*)))
}
/// Use the `format!` syntax to write data into a buffer of type `&mut Writer`.
/// See `std::fmt` for more information.
///
/// # Example
///
/// ```
/// # #![allow(unused_must_use)]
///
/// let mut w = Vec::new();
/// write!(&mut w, "test");
/// write!(&mut w, "formatted {}", "arguments");
/// ```
#[macro_export]
#[stable]
macro_rules! write {
($dst:expr, $($arg:tt)*) => ((&mut *$dst).write_fmt(format_args!($($arg)*)))
}
/// Equivalent to the `write!` macro, except that a newline is appended after
/// the message is written.
#[macro_export]
#[stable]
macro_rules! writeln {
($dst:expr, $fmt:expr $($arg:tt)*) => (
write!($dst, concat!($fmt, "\n") $($arg)*)
)
}
/// Equivalent to the `println!` macro except that a newline is not printed at
/// the end of the message.
#[macro_export]
#[stable]
macro_rules! print {
($($arg:tt)*) => (::std::io::stdio::print_args(format_args!($($arg)*)))
}
/// Macro for printing to a task's stdout handle.
///
/// Each task can override its stdout handle via `std::io::stdio::set_stdout`.
/// The syntax of this macro is the same as that used for `format!`. For more
/// information, see `std::fmt` and `std::io::stdio`.
///
/// # Example
///
/// ```
/// println!("hello there!");
/// println!("format {} arguments", "some");
/// ```
#[macro_export]
#[stable]
macro_rules! println {
($($arg:tt)*) => (::std::io::stdio::println_args(format_args!($($arg)*)))
}
/// Helper macro for unwrapping `Result` values while returning early with an
/// error if the value of the expression is `Err`. For more information, see
/// `std::io`.
#[macro_export]
macro_rules! try {
($expr:expr) => ({
match $expr {
Ok(val) => val,
Err(err) => return Err(::std::error::FromError::from_error(err))
}
})
}
/// Create a `std::vec::Vec` containing the arguments.
#[macro_export]
macro_rules! vec {
($($x:expr),*) => ({
let xs: ::std::boxed::Box<[_]> = box [$($x),*];
::std::slice::SliceExt::into_vec(xs)
});
($($x:expr,)*) => (vec![$($x),*])
}
/// A macro to select an event from a number of receivers.
///
/// This macro is used to wait for the first event to occur on a number of
/// receivers. It places no restrictions on the types of receivers given to
/// this macro, this can be viewed as a heterogeneous select.
///
/// # Example
///
/// ```
/// use std::thread::Thread;
/// use std::sync::mpsc::channel;
///
/// let (tx1, rx1) = channel();
/// let (tx2, rx2) = channel();
/// # fn long_running_task() {}
/// # fn calculate_the_answer() -> int { 42i }
///
/// Thread::spawn(move|| { long_running_task(); tx1.send(()) }).detach();
/// Thread::spawn(move|| { tx2.send(calculate_the_answer()) }).detach();
///
/// select! (
/// _ = rx1.recv() => println!("the long running task finished first"),
/// answer = rx2.recv() => {
/// println!("the answer was: {}", answer.unwrap());
/// }
/// )
/// ```
///
/// For more information about select, see the `std::sync::mpsc::Select` structure.
#[macro_export]
#[experimental]
macro_rules! select {
(
$($name:pat = $rx:ident.$meth:ident() => $code:expr),+
) => ({
use std::sync::mpsc::Select;
let sel = Select::new();
$( let mut $rx = sel.handle(&$rx); )+
unsafe {
$( $rx.add(); )+
}
let ret = sel.wait();
$( if ret == $rx.id() { let $name = $rx.$meth(); $code } else )+
{ unreachable!() }
})
}
// When testing the standard library, we link to the liblog crate to get the
// logging macros. In doing so, the liblog crate was linked against the real
// version of libstd, and uses a different std::fmt module than the test crate
// uses. To get around this difference, we redefine the log!() macro here to be
// just a dumb version of what it should be.
#[cfg(test)]
macro_rules! log {
($lvl:expr, $($args:tt)*) => (
if log_enabled!($lvl) { println!($($args)*) }
)
}
/// Built-in macros to the compiler itself.
///
/// These macros do not have any corresponding definition with a `macro_rules!`
/// macro, but are documented here. Their implementations can be found hardcoded
/// into libsyntax itself.
#[cfg(dox)]
pub mod builtin {
/// The core macro for formatted string creation & output.
///
/// This macro produces a value of type `fmt::Arguments`. This value can be
/// passed to the functions in `std::fmt` for performing useful functions.
/// All other formatting macros (`format!`, `write!`, `println!`, etc) are
/// proxied through this one.
///
/// For more information, see the documentation in `std::fmt`.
///
/// # Example
///
/// ```rust
/// use std::fmt;
///
/// let s = fmt::format(format_args!("hello {}", "world"));
/// assert_eq!(s, format!("hello {}", "world"));
///
/// ```
#[macro_export]
macro_rules! format_args { ($fmt:expr $($args:tt)*) => ({
/* compiler built-in */
}) }
/// Inspect an environment variable at compile time.
///
/// This macro will expand to the value of the named environment variable at
/// compile time, yielding an expression of type `&'static str`.
///
/// If the environment variable is not defined, then a compilation error
/// will be emitted. To not emit a compile error, use the `option_env!`
/// macro instead.
///
/// # Example
///
/// ```rust
/// let path: &'static str = env!("PATH");
/// println!("the $PATH variable at the time of compiling was: {}", path);
/// ```
#[macro_export]
macro_rules! env { ($name:expr) => ({ /* compiler built-in */ }) }
/// Optionally inspect an environment variable at compile time.
///
/// If the named environment variable is present at compile time, this will
/// expand into an expression of type `Option<&'static str>` whose value is
/// `Some` of the value of the environment variable. If the environment
/// variable is not present, then this will expand to `None`.
///
/// A compile time error is never emitted when using this macro regardless
/// of whether the environment variable is present or not.
///
/// # Example
///
/// ```rust
/// let key: Option<&'static str> = option_env!("SECRET_KEY");
/// println!("the secret key might be: {}", key);
/// ```
#[macro_export]
macro_rules! option_env { ($name:expr) => ({ /* compiler built-in */ }) }
/// Concatenate literals into a static byte slice.
///
/// This macro takes any number of comma-separated literal expressions,
/// yielding an expression of type `&'static [u8]` which is the
/// concatenation (left to right) of all the literals in their byte format.
///
/// This extension currently only supports string literals, character
/// literals, and integers less than 256. The byte slice returned is the
/// utf8-encoding of strings and characters.
///
/// # Example
///
/// ```
/// let rust = bytes!("r", 'u', "st", 255);
/// assert_eq!(rust[1], b'u');
/// assert_eq!(rust[4], 255);
/// ```
#[macro_export]
macro_rules! bytes { ($($e:expr),*) => ({ /* compiler built-in */ }) }
/// Concatenate identifiers into one identifier.
///
/// This macro takes any number of comma-separated identifiers, and
/// concatenates them all into one, yielding an expression which is a new
/// identifier. Note that hygiene makes it such that this macro cannot
/// capture local variables, and macros are only allowed in item,
/// statement or expression position, meaning this macro may be difficult to
/// use in some situations.
///
/// # Example
///
/// ```
/// #![feature(concat_idents)]
///
/// # fn main() {
/// fn foobar() -> int { 23 }
///
/// let f = concat_idents!(foo, bar);
/// println!("{}", f());
/// # }
/// ```
#[macro_export]
macro_rules! concat_idents {
($($e:ident),*) => ({ /* compiler built-in */ })
}
/// Concatenates literals into a static string slice.
///
/// This macro takes any number of comma-separated literals, yielding an
/// expression of type `&'static str` which represents all of the literals
/// concatenated left-to-right.
///
/// Integer and floating point literals are stringified in order to be
/// concatenated.
///
/// # Example
///
/// ```
/// let s = concat!("test", 10i, 'b', true);
/// assert_eq!(s, "test10btrue");
/// ```
#[macro_export]
macro_rules! concat { ($($e:expr),*) => ({ /* compiler built-in */ }) }
/// A macro which expands to the line number on which it was invoked.
///
/// The expanded expression has type `uint`, and the returned line is not
/// the invocation of the `line!()` macro itself, but rather the first macro
/// invocation leading up to the invocation of the `line!()` macro.
///
/// # Example
///
/// ```
/// let current_line = line!();
/// println!("defined on line: {}", current_line);
/// ```
#[macro_export]
macro_rules! line { () => ({ /* compiler built-in */ }) }
/// A macro which expands to the column number on which it was invoked.
///
/// The expanded expression has type `uint`, and the returned column is not
/// the invocation of the `column!()` macro itself, but rather the first macro
/// invocation leading up to the invocation of the `column!()` macro.
///
/// # Example
///
/// ```
/// let current_col = column!();
/// println!("defined on column: {}", current_col);
/// ```
#[macro_export]
macro_rules! column { () => ({ /* compiler built-in */ }) }
/// A macro which expands to the file name from which it was invoked.
///
/// The expanded expression has type `&'static str`, and the returned file
/// is not the invocation of the `file!()` macro itself, but rather the
/// first macro invocation leading up to the invocation of the `file!()`
/// macro.
///
/// # Example
///
/// ```
/// let this_file = file!();
/// println!("defined in file: {}", this_file);
/// ```
#[macro_export]
macro_rules! file { () => ({ /* compiler built-in */ }) }
/// A macro which stringifies its argument.
///
/// This macro will yield an expression of type `&'static str` which is the
/// stringification of all the tokens passed to the macro. No restrictions
/// are placed on the syntax of the macro invocation itself.
///
/// # Example
///
/// ```
/// let one_plus_one = stringify!(1 + 1);
/// assert_eq!(one_plus_one, "1 + 1");
/// ```
#[macro_export]
macro_rules! stringify { ($t:tt) => ({ /* compiler built-in */ }) }
/// Includes a utf8-encoded file as a string.
///
/// This macro will yield an expression of type `&'static str` which is the
/// contents of the filename specified. The file is located relative to the
/// current file (similarly to how modules are found),
///
/// # Example
///
/// ```rust,ignore
/// let secret_key = include_str!("secret-key.ascii");
/// ```
#[macro_export]
macro_rules! include_str { ($file:expr) => ({ /* compiler built-in */ }) }
/// Includes a file as a byte slice.
///
/// This macro will yield an expression of type `&'static [u8]` which is
/// the contents of the filename specified. The file is located relative to
/// the current file (similarly to how modules are found),
///
/// # Example
///
/// ```rust,ignore
/// let secret_key = include_bytes!("secret-key.bin");
/// ```
#[macro_export]
macro_rules! include_bytes { ($file:expr) => ({ /* compiler built-in */ }) }
/// Deprecated alias for `include_bytes!()`.
#[macro_export]
macro_rules! include_bin { ($file:expr) => ({ /* compiler built-in */}) }
/// Expands to a string that represents the current module path.
///
/// The current module path can be thought of as the hierarchy of modules
/// leading back up to the crate root. The first component of the path
/// returned is the name of the crate currently being compiled.
///
/// # Example
///
/// ```rust
/// mod test {
/// pub fn foo() {
/// assert!(module_path!().ends_with("test"));
/// }
/// }
///
/// test::foo();
/// ```
#[macro_export]
macro_rules! module_path { () => ({ /* compiler built-in */ }) }
/// Boolean evaluation of configuration flags.
///
/// In addition to the `#[cfg]` attribute, this macro is provided to allow
/// boolean expression evaluation of configuration flags. This frequently
/// leads to less duplicated code.
///
/// The syntax given to this macro is the same syntax as the `cfg`
/// attribute.
///
/// # Example
///
/// ```rust
/// let my_directory = if cfg!(windows) {
/// "windows-specific-directory"
/// } else {
/// "unix-directory"
/// };
/// ```
#[macro_export]
macro_rules! cfg { ($cfg:tt) => ({ /* compiler built-in */ }) }
}

View File

@ -23,11 +23,14 @@ mod imp {
use path::Path;
use rand::Rng;
use rand::reader::ReaderRng;
use result::Result::{Ok, Err};
use result::Result::Ok;
use slice::SliceExt;
use mem;
use os::errno;
// NOTE: for old macros; remove after the next snapshot
#[cfg(stage0)] use result::Result::Err;
#[cfg(all(target_os = "linux",
any(target_arch = "x86_64",
target_arch = "x86",

View File

@ -17,8 +17,10 @@ use ops::{Add, Sub, Mul, Div, Neg, FnOnce};
use option::Option;
use option::Option::{Some, None};
use num::Int;
use result::Result;
use result::Result::{Ok, Err};
use result::Result::Ok;
// NOTE: for old macros; remove after the next snapshot
#[cfg(stage0)] use result::Result::Err;
/// The number of nanoseconds in a microsecond.
const NANOS_PER_MICRO: i32 = 1000;

View File

@ -0,0 +1,39 @@
// 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.
#![feature(phase, lang_items)]
#![no_std]
#[phase(plugin, link)]
extern crate core;
extern crate libc;
#[phase(plugin, link)]
extern crate collections;
use core::option::Option::Some;
use core::slice::SliceExt;
use collections::vec::Vec;
#[lang = "stack_exhausted"] extern fn stack_exhausted() {}
#[lang = "eh_personality"] extern fn eh_personality() {}
#[lang = "panic_fmt"] fn panic_fmt() -> ! { loop {} }
// Issue #16806
#[start]
fn start(_argc: int, _argv: *const *const u8) -> int {
let x: Vec<u8> = vec![0, 1, 2];
match x.last() {
Some(&2) => (),
_ => panic!(),
}
0
}