<commit_before>// Copyright 2012 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.

//! Primitive traits representing basic 'kinds' of types
//!
//! Rust types can be classified in various useful ways according to
//! intrinsic properties of the type. These classifications, often called
//! 'kinds', are represented as traits.
//!
//! They cannot be implemented by user code, but are instead implemented
//! by the compiler automatically for the types to which they apply.

/// Types able to be transferred across task boundaries.
#[lang="send"]
pub trait Send for Sized? : 'static {
    // empty.
}

/// Types with a constant size known at compile-time.
#[lang="sized"]
pub trait Sized for Sized? {
    // Empty.
}

/// Types that can be copied by simply copying bits (i.e. `memcpy`).
#[lang="copy"]
pub trait Copy for Sized? {
    // Empty.
}

/// Types that can be safely shared between tasks when aliased.
///
/// The precise definition is: a type `T` is `Sync` if `&T` is
/// thread-safe. In other words, there is no possibility of data races
/// when passing `&T` references between tasks.
///
/// As one would expect, primitive types like `u8` and `f64` are all
/// `Sync`, and so are simple aggregate types containing them (like
/// tuples, structs and enums). More instances of basic `Sync` types
/// include "immutable" types like `&T` and those with simple
/// inherited mutability, such as `Box<T>`, `Vec<T>` and most other
/// collection types. (Generic parameters need to be `Sync` for their
/// container to be `Sync`.)
///
/// A somewhat surprising consequence of the definition is `&mut T` is
/// `Sync` (if `T` is `Sync`) even though it seems that it might
/// provide unsynchronised mutation. The trick is a mutable reference
/// stored in an aliasable reference (that is, `& &mut T`) becomes
/// read-only, as if it were a `& &T`, hence there is no risk of a data
/// race.
///
/// Types that are not `Sync` are those that have "interior
/// mutability" in a non-thread-safe way, such as `Cell` and `RefCell`
/// in `std::cell`. These types allow for mutation of their contents
/// even when in an immutable, aliasable slot, e.g. the contents of
/// `&Cell<T>` can be `.set`, and do not ensure data races are
/// impossible, hence they cannot be `Sync`. A higher level example
/// of a non-`Sync` type is the reference counted pointer
/// `std::rc::Rc`, because any reference `&Rc<T>` can clone a new
/// reference, which modifies the reference counts in a non-atomic
/// way.
///
/// For cases when one does need thread-safe interior mutability,
/// types like the atomics in `std::sync` and `Mutex` & `RWLock` in
/// the `sync` crate do ensure that any mutation cannot cause data
/// races.  Hence these types are `Sync`.
///
/// Users writing their own types with interior mutability (or anything
/// else that is not thread-safe) should use the `NoSync` marker type
/// (from `std::kinds::marker`) to ensure that the compiler doesn't
/// consider the user-defined type to be `Sync`.  Any types with
/// interior mutability must also use the `std::cell::UnsafeCell` wrapper
/// around the value(s) which can be mutated when behind a `&`
/// reference; not doing this is undefined behaviour (for example,
/// `transmute`-ing from `&T` to `&mut T` is illegal).
#[lang="sync"]
pub trait Sync for Sized? {
    // Empty
}

/// Marker types are special types that are used with unsafe code to
/// inform the compiler of special constraints. Marker types should
/// only be needed when you are creating an abstraction that is
/// implemented using unsafe code. In that case, you may want to embed
/// some of the marker types below into your type.
pub mod marker {
    use super::Copy;

    /// A marker type whose type parameter `T` is considered to be
    /// covariant with respect to the type itself. This is (typically)
    /// used to indicate that an instance of the type `T` is being stored
    /// into memory and read from, even though that may not be apparent.
    ///
    /// For more information about variance, refer to this Wikipedia
    /// article <http://en.wikipedia.org/wiki/Variance_%28computer_science%29>.
    ///
    /// *Note:* It is very unusual to have to add a covariant constraint.
    /// If you are not sure, you probably want to use `InvariantType`.
    ///
    /// # Example
    ///
    /// Given a struct `S` that includes a type parameter `T`
    /// but does not actually *reference* that type parameter:
    ///
    /// ```ignore
    /// use std::mem;
    ///
    /// struct S<T> { x: *() }
    /// fn get<T>(s: &S<T>) -> T {
    ///    unsafe {
    ///        let x: *T = mem::transmute(s.x);
    ///        *x
    ///    }
    /// }
    /// ```
    ///
    /// The type system would currently infer that the value of
    /// the type parameter `T` is irrelevant, and hence a `S<int>` is
    /// a subtype of `S<Box<int>>` (or, for that matter, `S<U>` for
    /// any `U`). But this is incorrect because `get()` converts the
    /// `*()` into a `*T` and reads from it. Therefore, we should include the
    /// a marker field `CovariantType<T>` to inform the type checker that
    /// `S<T>` is a subtype of `S<U>` if `T` is a subtype of `U`
    /// (for example, `S<&'static int>` is a subtype of `S<&'a int>`
    /// for some lifetime `'a`, but not the other way around).
    #[lang="covariant_type"]
    #[deriving(Clone, PartialEq, Eq, PartialOrd, Ord)]
    pub struct CovariantType<T>;

    impl<T> Copy for CovariantType<T> {}

    /// A marker type whose type parameter `T` is considered to be
    /// contravariant with respect to the type itself. This is (typically)
    /// used to indicate that an instance of the type `T` will be consumed
    /// (but not read from), even though that may not be apparent.
    ///
    /// For more information about variance, refer to this Wikipedia
    /// article <http://en.wikipedia.org/wiki/Variance_%28computer_science%29>.
    ///
    /// *Note:* It is very unusual to have to add a contravariant constraint.
    /// If you are not sure, you probably want to use `InvariantType`.
    ///
    /// # Example
    ///
    /// Given a struct `S` that includes a type parameter `T`
    /// but does not actually *reference* that type parameter:
    ///
    /// ```
    /// use std::mem;
    ///
    /// struct S<T> { x: *const () }
    /// fn get<T>(s: &S<T>, v: T) {
    ///    unsafe {
    ///        let x: fn(T) = mem::transmute(s.x);
    ///        x(v)
    ///    }
    /// }
    /// ```
    ///
    /// The type system would currently infer that the value of
    /// the type parameter `T` is irrelevant, and hence a `S<int>` is
    /// a subtype of `S<Box<int>>` (or, for that matter, `S<U>` for
    /// any `U`). But this is incorrect because `get()` converts the
    /// `*()` into a `fn(T)` and then passes a value of type `T` to it.
    ///
    /// Supplying a `ContravariantType` marker would correct the
    /// problem, because it would mark `S` so that `S<T>` is only a
    /// subtype of `S<U>` if `U` is a subtype of `T`; given that the
    /// function requires arguments of type `T`, it must also accept
    /// arguments of type `U`, hence such a conversion is safe.
    #[lang="contravariant_type"]
    #[deriving(Clone, PartialEq, Eq, PartialOrd, Ord)]
    pub struct ContravariantType<T>;

    impl<T> Copy for ContravariantType<T> {}

    /// A marker type whose type parameter `T` is considered to be
    /// invariant with respect to the type itself. This is (typically)
    /// used to indicate that instances of the type `T` may be read or
    /// written, even though that may not be apparent.
    ///
    /// For more information about variance, refer to this Wikipedia
    /// article <http://en.wikipedia.org/wiki/Variance_%28computer_science%29>.
    ///
    /// # Example
    ///
    /// The Cell type is an example which uses unsafe code to achieve
    /// "interior" mutability:
    ///
    /// ```
    /// pub struct Cell<T> { value: T }
    /// # fn main() {}
    /// ```
    ///
    /// The type system would infer that `value` is only read here and
    /// never written, but in fact `Cell` uses unsafe code to achieve
    /// interior mutability.
    #[lang="invariant_type"]
    #[deriving(Clone, PartialEq, Eq, PartialOrd, Ord)]
    pub struct InvariantType<T>;

    impl<T> Copy for InvariantType<T> {}

    /// As `CovariantType`, but for lifetime parameters. Using
    /// `CovariantLifetime<'a>` indicates that it is ok to substitute
    /// a *longer* lifetime for `'a` than the one you originally
    /// started with (e.g., you could convert any lifetime `'foo` to
    /// `'static`). You almost certainly want `ContravariantLifetime`
    /// instead, or possibly `InvariantLifetime`. The only case where
    /// it would be appropriate is that you have a (type-casted, and
    /// hence hidden from the type system) function pointer with a
    /// signature like `fn(&'a T)` (and no other uses of `'a`). In
    /// this case, it is ok to substitute a larger lifetime for `'a`
    /// (e.g., `fn(&'static T)`), because the function is only
    /// becoming more selective in terms of what it accepts as
    /// argument.
    ///
    /// For more information about variance, refer to this Wikipedia
    /// article <http://en.wikipedia.org/wiki/Variance_%28computer_science%29>.
    #[lang="covariant_lifetime"]
    #[deriving(Clone, PartialEq, Eq, PartialOrd, Ord)]
    pub struct CovariantLifetime<'a>;

    impl<'a> Copy for CovariantLifetime<'a> {}

    /// As `ContravariantType`, but for lifetime parameters. Using
    /// `ContravariantLifetime<'a>` indicates that it is ok to
    /// substitute a *shorter* lifetime for `'a` than the one you
    /// originally started with (e.g., you could convert `'static` to
    /// any lifetime `'foo`). This is appropriate for cases where you
    /// have an unsafe pointer that is actually a pointer into some
    /// memory with lifetime `'a`, and thus you want to limit the
    /// lifetime of your data structure to `'a`. An example of where
    /// this is used is the iterator for vectors.
    ///
    /// For more information about variance, refer to this Wikipedia
    /// article <http://en.wikipedia.org/wiki/Variance_%28computer_science%29>.
    #[lang="contravariant_lifetime"]
    #[deriving(Clone, PartialEq, Eq, PartialOrd, Ord)]
    pub struct ContravariantLifetime<'a>;

    impl<'a> Copy for ContravariantLifetime<'a> {}

    /// As `InvariantType`, but for lifetime parameters. Using
    /// `InvariantLifetime<'a>` indicates that it is not ok to
    /// substitute any other lifetime for `'a` besides its original
    /// value. This is appropriate for cases where you have an unsafe
    /// pointer that is actually a pointer into memory with lifetime `'a`,
    /// and this pointer is itself stored in an inherently mutable
    /// location (such as a `Cell`).
    #[lang="invariant_lifetime"]
    #[deriving(Clone, PartialEq, Eq, PartialOrd, Ord)]
    pub struct InvariantLifetime<'a>;

    impl<'a> Copy for InvariantLifetime<'a> {}

    /// A type which is considered "not sendable", meaning that it cannot
    /// be safely sent between tasks, even if it is owned. This is
    /// typically embedded in other types, such as `Gc`, to ensure that
    /// their instances remain thread-local.
    #[lang="no_send_bound"]
    #[deriving(Clone, PartialEq, Eq, PartialOrd, Ord)]
    #[allow(missing_copy_implementations)]
    pub struct NoSend;

    /// A type which is considered "not POD", meaning that it is not
    /// implicitly copyable. This is typically embedded in other types to
    /// ensure that they are never copied, even if they lack a destructor.
    #[lang="no_copy_bound"]
    #[deriving(Clone, PartialEq, Eq, PartialOrd, Ord)]
    #[allow(missing_copy_implementations)]
    pub struct NoCopy;

    /// A type which is considered "not sync", meaning that
    /// its contents are not threadsafe, hence they cannot be
    /// shared between tasks.
    #[lang="no_sync_bound"]
    #[deriving(Clone, PartialEq, Eq, PartialOrd, Ord)]
    #[allow(missing_copy_implementations)]
    pub struct NoSync;

    /// A type which is considered managed by the GC. This is typically
    /// embedded in other types.
    #[lang="managed_bound"]
    #[deriving(Clone, PartialEq, Eq, PartialOrd, Ord)]
    #[allow(missing_copy_implementations)]
    pub struct Managed;
}

<commit_msg>rollup merge of #19860: japaric/copy-markers<commit_after>// Copyright 2012 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.

//! Primitive traits representing basic 'kinds' of types
//!
//! Rust types can be classified in various useful ways according to
//! intrinsic properties of the type. These classifications, often called
//! 'kinds', are represented as traits.
//!
//! They cannot be implemented by user code, but are instead implemented
//! by the compiler automatically for the types to which they apply.

/// Types able to be transferred across task boundaries.
#[lang="send"]
pub trait Send for Sized? : 'static {
    // empty.
}

/// Types with a constant size known at compile-time.
#[lang="sized"]
pub trait Sized for Sized? {
    // Empty.
}

/// Types that can be copied by simply copying bits (i.e. `memcpy`).
#[lang="copy"]
pub trait Copy for Sized? {
    // Empty.
}

/// Types that can be safely shared between tasks when aliased.
///
/// The precise definition is: a type `T` is `Sync` if `&T` is
/// thread-safe. In other words, there is no possibility of data races
/// when passing `&T` references between tasks.
///
/// As one would expect, primitive types like `u8` and `f64` are all
/// `Sync`, and so are simple aggregate types containing them (like
/// tuples, structs and enums). More instances of basic `Sync` types
/// include "immutable" types like `&T` and those with simple
/// inherited mutability, such as `Box<T>`, `Vec<T>` and most other
/// collection types. (Generic parameters need to be `Sync` for their
/// container to be `Sync`.)
///
/// A somewhat surprising consequence of the definition is `&mut T` is
/// `Sync` (if `T` is `Sync`) even though it seems that it might
/// provide unsynchronised mutation. The trick is a mutable reference
/// stored in an aliasable reference (that is, `& &mut T`) becomes
/// read-only, as if it were a `& &T`, hence there is no risk of a data
/// race.
///
/// Types that are not `Sync` are those that have "interior
/// mutability" in a non-thread-safe way, such as `Cell` and `RefCell`
/// in `std::cell`. These types allow for mutation of their contents
/// even when in an immutable, aliasable slot, e.g. the contents of
/// `&Cell<T>` can be `.set`, and do not ensure data races are
/// impossible, hence they cannot be `Sync`. A higher level example
/// of a non-`Sync` type is the reference counted pointer
/// `std::rc::Rc`, because any reference `&Rc<T>` can clone a new
/// reference, which modifies the reference counts in a non-atomic
/// way.
///
/// For cases when one does need thread-safe interior mutability,
/// types like the atomics in `std::sync` and `Mutex` & `RWLock` in
/// the `sync` crate do ensure that any mutation cannot cause data
/// races.  Hence these types are `Sync`.
///
/// Users writing their own types with interior mutability (or anything
/// else that is not thread-safe) should use the `NoSync` marker type
/// (from `std::kinds::marker`) to ensure that the compiler doesn't
/// consider the user-defined type to be `Sync`.  Any types with
/// interior mutability must also use the `std::cell::UnsafeCell` wrapper
/// around the value(s) which can be mutated when behind a `&`
/// reference; not doing this is undefined behaviour (for example,
/// `transmute`-ing from `&T` to `&mut T` is illegal).
#[lang="sync"]
pub trait Sync for Sized? {
    // Empty
}

/// Marker types are special types that are used with unsafe code to
/// inform the compiler of special constraints. Marker types should
/// only be needed when you are creating an abstraction that is
/// implemented using unsafe code. In that case, you may want to embed
/// some of the marker types below into your type.
pub mod marker {
    use super::Copy;

    /// A marker type whose type parameter `T` is considered to be
    /// covariant with respect to the type itself. This is (typically)
    /// used to indicate that an instance of the type `T` is being stored
    /// into memory and read from, even though that may not be apparent.
    ///
    /// For more information about variance, refer to this Wikipedia
    /// article <http://en.wikipedia.org/wiki/Variance_%28computer_science%29>.
    ///
    /// *Note:* It is very unusual to have to add a covariant constraint.
    /// If you are not sure, you probably want to use `InvariantType`.
    ///
    /// # Example
    ///
    /// Given a struct `S` that includes a type parameter `T`
    /// but does not actually *reference* that type parameter:
    ///
    /// ```ignore
    /// use std::mem;
    ///
    /// struct S<T> { x: *() }
    /// fn get<T>(s: &S<T>) -> T {
    ///    unsafe {
    ///        let x: *T = mem::transmute(s.x);
    ///        *x
    ///    }
    /// }
    /// ```
    ///
    /// The type system would currently infer that the value of
    /// the type parameter `T` is irrelevant, and hence a `S<int>` is
    /// a subtype of `S<Box<int>>` (or, for that matter, `S<U>` for
    /// any `U`). But this is incorrect because `get()` converts the
    /// `*()` into a `*T` and reads from it. Therefore, we should include the
    /// a marker field `CovariantType<T>` to inform the type checker that
    /// `S<T>` is a subtype of `S<U>` if `T` is a subtype of `U`
    /// (for example, `S<&'static int>` is a subtype of `S<&'a int>`
    /// for some lifetime `'a`, but not the other way around).
    #[lang="covariant_type"]
    #[deriving(Clone, PartialEq, Eq, PartialOrd, Ord)]
    pub struct CovariantType<T>;

    impl<T> Copy for CovariantType<T> {}

    /// A marker type whose type parameter `T` is considered to be
    /// contravariant with respect to the type itself. This is (typically)
    /// used to indicate that an instance of the type `T` will be consumed
    /// (but not read from), even though that may not be apparent.
    ///
    /// For more information about variance, refer to this Wikipedia
    /// article <http://en.wikipedia.org/wiki/Variance_%28computer_science%29>.
    ///
    /// *Note:* It is very unusual to have to add a contravariant constraint.
    /// If you are not sure, you probably want to use `InvariantType`.
    ///
    /// # Example
    ///
    /// Given a struct `S` that includes a type parameter `T`
    /// but does not actually *reference* that type parameter:
    ///
    /// ```
    /// use std::mem;
    ///
    /// struct S<T> { x: *const () }
    /// fn get<T>(s: &S<T>, v: T) {
    ///    unsafe {
    ///        let x: fn(T) = mem::transmute(s.x);
    ///        x(v)
    ///    }
    /// }
    /// ```
    ///
    /// The type system would currently infer that the value of
    /// the type parameter `T` is irrelevant, and hence a `S<int>` is
    /// a subtype of `S<Box<int>>` (or, for that matter, `S<U>` for
    /// any `U`). But this is incorrect because `get()` converts the
    /// `*()` into a `fn(T)` and then passes a value of type `T` to it.
    ///
    /// Supplying a `ContravariantType` marker would correct the
    /// problem, because it would mark `S` so that `S<T>` is only a
    /// subtype of `S<U>` if `U` is a subtype of `T`; given that the
    /// function requires arguments of type `T`, it must also accept
    /// arguments of type `U`, hence such a conversion is safe.
    #[lang="contravariant_type"]
    #[deriving(Clone, PartialEq, Eq, PartialOrd, Ord)]
    pub struct ContravariantType<T>;

    impl<T> Copy for ContravariantType<T> {}

    /// A marker type whose type parameter `T` is considered to be
    /// invariant with respect to the type itself. This is (typically)
    /// used to indicate that instances of the type `T` may be read or
    /// written, even though that may not be apparent.
    ///
    /// For more information about variance, refer to this Wikipedia
    /// article <http://en.wikipedia.org/wiki/Variance_%28computer_science%29>.
    ///
    /// # Example
    ///
    /// The Cell type is an example which uses unsafe code to achieve
    /// "interior" mutability:
    ///
    /// ```
    /// pub struct Cell<T> { value: T }
    /// # fn main() {}
    /// ```
    ///
    /// The type system would infer that `value` is only read here and
    /// never written, but in fact `Cell` uses unsafe code to achieve
    /// interior mutability.
    #[lang="invariant_type"]
    #[deriving(Clone, PartialEq, Eq, PartialOrd, Ord)]
    pub struct InvariantType<T>;

    impl<T> Copy for InvariantType<T> {}

    /// As `CovariantType`, but for lifetime parameters. Using
    /// `CovariantLifetime<'a>` indicates that it is ok to substitute
    /// a *longer* lifetime for `'a` than the one you originally
    /// started with (e.g., you could convert any lifetime `'foo` to
    /// `'static`). You almost certainly want `ContravariantLifetime`
    /// instead, or possibly `InvariantLifetime`. The only case where
    /// it would be appropriate is that you have a (type-casted, and
    /// hence hidden from the type system) function pointer with a
    /// signature like `fn(&'a T)` (and no other uses of `'a`). In
    /// this case, it is ok to substitute a larger lifetime for `'a`
    /// (e.g., `fn(&'static T)`), because the function is only
    /// becoming more selective in terms of what it accepts as
    /// argument.
    ///
    /// For more information about variance, refer to this Wikipedia
    /// article <http://en.wikipedia.org/wiki/Variance_%28computer_science%29>.
    #[lang="covariant_lifetime"]
    #[deriving(Clone, PartialEq, Eq, PartialOrd, Ord)]
    pub struct CovariantLifetime<'a>;

    impl<'a> Copy for CovariantLifetime<'a> {}

    /// As `ContravariantType`, but for lifetime parameters. Using
    /// `ContravariantLifetime<'a>` indicates that it is ok to
    /// substitute a *shorter* lifetime for `'a` than the one you
    /// originally started with (e.g., you could convert `'static` to
    /// any lifetime `'foo`). This is appropriate for cases where you
    /// have an unsafe pointer that is actually a pointer into some
    /// memory with lifetime `'a`, and thus you want to limit the
    /// lifetime of your data structure to `'a`. An example of where
    /// this is used is the iterator for vectors.
    ///
    /// For more information about variance, refer to this Wikipedia
    /// article <http://en.wikipedia.org/wiki/Variance_%28computer_science%29>.
    #[lang="contravariant_lifetime"]
    #[deriving(Clone, PartialEq, Eq, PartialOrd, Ord)]
    pub struct ContravariantLifetime<'a>;

    impl<'a> Copy for ContravariantLifetime<'a> {}

    /// As `InvariantType`, but for lifetime parameters. Using
    /// `InvariantLifetime<'a>` indicates that it is not ok to
    /// substitute any other lifetime for `'a` besides its original
    /// value. This is appropriate for cases where you have an unsafe
    /// pointer that is actually a pointer into memory with lifetime `'a`,
    /// and this pointer is itself stored in an inherently mutable
    /// location (such as a `Cell`).
    #[lang="invariant_lifetime"]
    #[deriving(Clone, PartialEq, Eq, PartialOrd, Ord)]
    pub struct InvariantLifetime<'a>;

    impl<'a> Copy for InvariantLifetime<'a> {}

    /// A type which is considered "not sendable", meaning that it cannot
    /// be safely sent between tasks, even if it is owned. This is
    /// typically embedded in other types, such as `Gc`, to ensure that
    /// their instances remain thread-local.
    #[lang="no_send_bound"]
    #[deriving(Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
    pub struct NoSend;

    /// A type which is considered "not POD", meaning that it is not
    /// implicitly copyable. This is typically embedded in other types to
    /// ensure that they are never copied, even if they lack a destructor.
    #[lang="no_copy_bound"]
    #[deriving(Clone, PartialEq, Eq, PartialOrd, Ord)]
    #[allow(missing_copy_implementations)]
    pub struct NoCopy;

    /// A type which is considered "not sync", meaning that
    /// its contents are not threadsafe, hence they cannot be
    /// shared between tasks.
    #[lang="no_sync_bound"]
    #[deriving(Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
    pub struct NoSync;

    /// A type which is considered managed by the GC. This is typically
    /// embedded in other types.
    #[lang="managed_bound"]
    #[deriving(Clone, PartialEq, Eq, PartialOrd, Ord)]
    #[allow(missing_copy_implementations)]
    pub struct Managed;
}

<|endoftext|>


<commit_before>// 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.

#![unstable(feature = "std_misc")]

/// 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.
///
/// # Examples
///
/// ```should_fail
/// # #![allow(unreachable_code)]
/// panic!();
/// panic!("this is a terrible mistake!");
/// panic!(4); // panic with the value of 4 to be collected elsewhere
/// panic!("this is a {} {message}", "fancy", message = "message");
/// ```
#[macro_export]
#[stable(feature = "rust1", since = "1.0.0")]
macro_rules! panic {
    () => ({
        panic!("explicit panic")
    });
    ($msg:expr) => ({
        $crate::rt::begin_unwind($msg, {
            // static requires less code at runtime, more constant data
            static _FILE_LINE: (&'static str, usize) = (file!(), line!() as usize);
            &_FILE_LINE
        })
    });
    ($fmt:expr, $($arg:tt)+) => ({
        $crate::rt::begin_unwind_fmt(format_args!($fmt, $($arg)+), {
            // 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, usize) = (file!(), line!() as usize);
            &_FILE_LINE
        })
    });
}

/// 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.
#[macro_export]
#[stable(feature = "rust1", since = "1.0.0")]
#[allow_internal_unstable]
macro_rules! print {
    ($($arg:tt)*) => ($crate::io::_print(format_args!($($arg)*)));
}

/// Macro for printing to the standard output.
///
/// Use the `format!` syntax to write data to the standard output.
/// See `std::fmt` for more information.
///
/// # Examples
///
/// ```
/// println!("hello there!");
/// println!("format {} arguments", "some");
/// ```
#[macro_export]
#[stable(feature = "rust1", since = "1.0.0")]
macro_rules! println {
    ($fmt:expr) => (print!(concat!($fmt, "\n")));
    ($fmt:expr, $($arg:tt)*) => (print!(concat!($fmt, "\n"), $($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]
#[stable(feature = "rust1", since = "1.0.0")]
macro_rules! try {
    ($expr:expr) => (match $expr {
        $crate::result::Result::Ok(val) => val,
        $crate::result::Result::Err(err) => {
            return $crate::result::Result::Err($crate::error::FromError::from_error(err))
        }
    })
}

/// 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.
///
/// # Examples
///
/// ```
/// use std::thread;
/// use std::sync::mpsc;
///
/// // two placeholder functions for now
/// fn long_running_task() {}
/// fn calculate_the_answer() -> u32 { 42 }
///
/// let (tx1, rx1) = mpsc::channel();
/// let (tx2, rx2) = mpsc::channel();
///
/// thread::spawn(move|| { long_running_task(); tx1.send(()).unwrap(); });
/// thread::spawn(move|| { tx2.send(calculate_the_answer()).unwrap(); });
///
/// 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]
#[unstable(feature = "std_misc")]
macro_rules! select {
    (
        $($name:pat = $rx:ident.$meth:ident() => $code:expr),+
    ) => ({
        use $crate::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`.
    ///
    /// # Examples
    ///
    /// ```
    /// 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.
    ///
    /// # Examples
    ///
    /// ```
    /// 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.
    ///
    /// # Examples
    ///
    /// ```
    /// 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 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.
    ///
    /// # Examples
    ///
    /// ```
    /// #![feature(concat_idents)]
    ///
    /// # fn main() {
    /// fn foobar() -> u32 { 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.
    ///
    /// # Examples
    ///
    /// ```
    /// let s = concat!("test", 10, '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 `usize`, 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.
    ///
    /// # Examples
    ///
    /// ```
    /// 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 `usize`, 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.
    ///
    /// # Examples
    ///
    /// ```
    /// 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.
    ///
    /// # Examples
    ///
    /// ```
    /// 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.
    ///
    /// # Examples
    ///
    /// ```
    /// 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),
    ///
    /// # Examples
    ///
    /// ```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),
    ///
    /// # Examples
    ///
    /// ```rust,ignore
    /// let secret_key = include_bytes!("secret-key.bin");
    /// ```
    #[macro_export]
    macro_rules! include_bytes { ($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.
    ///
    /// # Examples
    ///
    /// ```
    /// 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.
    ///
    /// # Examples
    ///
    /// ```
    /// let my_directory = if cfg!(windows) {
    ///     "windows-specific-directory"
    /// } else {
    ///     "unix-directory"
    /// };
    /// ```
    #[macro_export]
    macro_rules! cfg { ($cfg:tt) => ({ /* compiler built-in */ }) }
}
<commit_msg>Document include!<commit_after>// 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.

#![unstable(feature = "std_misc")]

/// 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.
///
/// # Examples
///
/// ```should_fail
/// # #![allow(unreachable_code)]
/// panic!();
/// panic!("this is a terrible mistake!");
/// panic!(4); // panic with the value of 4 to be collected elsewhere
/// panic!("this is a {} {message}", "fancy", message = "message");
/// ```
#[macro_export]
#[stable(feature = "rust1", since = "1.0.0")]
macro_rules! panic {
    () => ({
        panic!("explicit panic")
    });
    ($msg:expr) => ({
        $crate::rt::begin_unwind($msg, {
            // static requires less code at runtime, more constant data
            static _FILE_LINE: (&'static str, usize) = (file!(), line!() as usize);
            &_FILE_LINE
        })
    });
    ($fmt:expr, $($arg:tt)+) => ({
        $crate::rt::begin_unwind_fmt(format_args!($fmt, $($arg)+), {
            // 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, usize) = (file!(), line!() as usize);
            &_FILE_LINE
        })
    });
}

/// 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.
#[macro_export]
#[stable(feature = "rust1", since = "1.0.0")]
#[allow_internal_unstable]
macro_rules! print {
    ($($arg:tt)*) => ($crate::io::_print(format_args!($($arg)*)));
}

/// Macro for printing to the standard output.
///
/// Use the `format!` syntax to write data to the standard output.
/// See `std::fmt` for more information.
///
/// # Examples
///
/// ```
/// println!("hello there!");
/// println!("format {} arguments", "some");
/// ```
#[macro_export]
#[stable(feature = "rust1", since = "1.0.0")]
macro_rules! println {
    ($fmt:expr) => (print!(concat!($fmt, "\n")));
    ($fmt:expr, $($arg:tt)*) => (print!(concat!($fmt, "\n"), $($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]
#[stable(feature = "rust1", since = "1.0.0")]
macro_rules! try {
    ($expr:expr) => (match $expr {
        $crate::result::Result::Ok(val) => val,
        $crate::result::Result::Err(err) => {
            return $crate::result::Result::Err($crate::error::FromError::from_error(err))
        }
    })
}

/// 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.
///
/// # Examples
///
/// ```
/// use std::thread;
/// use std::sync::mpsc;
///
/// // two placeholder functions for now
/// fn long_running_task() {}
/// fn calculate_the_answer() -> u32 { 42 }
///
/// let (tx1, rx1) = mpsc::channel();
/// let (tx2, rx2) = mpsc::channel();
///
/// thread::spawn(move|| { long_running_task(); tx1.send(()).unwrap(); });
/// thread::spawn(move|| { tx2.send(calculate_the_answer()).unwrap(); });
///
/// 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]
#[unstable(feature = "std_misc")]
macro_rules! select {
    (
        $($name:pat = $rx:ident.$meth:ident() => $code:expr),+
    ) => ({
        use $crate::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`.
    ///
    /// # Examples
    ///
    /// ```
    /// 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.
    ///
    /// # Examples
    ///
    /// ```
    /// 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.
    ///
    /// # Examples
    ///
    /// ```
    /// 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 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.
    ///
    /// # Examples
    ///
    /// ```
    /// #![feature(concat_idents)]
    ///
    /// # fn main() {
    /// fn foobar() -> u32 { 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.
    ///
    /// # Examples
    ///
    /// ```
    /// let s = concat!("test", 10, '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 `usize`, 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.
    ///
    /// # Examples
    ///
    /// ```
    /// 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 `usize`, 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.
    ///
    /// # Examples
    ///
    /// ```
    /// 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.
    ///
    /// # Examples
    ///
    /// ```
    /// 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.
    ///
    /// # Examples
    ///
    /// ```
    /// 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),
    ///
    /// # Examples
    ///
    /// ```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),
    ///
    /// # Examples
    ///
    /// ```rust,ignore
    /// let secret_key = include_bytes!("secret-key.bin");
    /// ```
    #[macro_export]
    macro_rules! include_bytes { ($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.
    ///
    /// # Examples
    ///
    /// ```
    /// 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.
    ///
    /// # Examples
    ///
    /// ```
    /// let my_directory = if cfg!(windows) {
    ///     "windows-specific-directory"
    /// } else {
    ///     "unix-directory"
    /// };
    /// ```
    #[macro_export]
    macro_rules! cfg { ($cfg:tt) => ({ /* compiler built-in */ }) }

    /// Parse the current given file as an expression.
    ///
    /// This is generally a bad idea, because it's going to behave unhygenically.
    ///
    /// # Examples
    ///
    /// ```ignore
    /// fn foo() {
    ///     include!("/path/to/a/file")
    /// }
    /// ```
    #[macro_export]
    macro_rules! include { ($cfg:tt) => ({ /* compiler built-in */ }) }
}
<|endoftext|>


<commit_before><commit_msg>Refactor build_triangle_renderable<commit_after><|endoftext|>


<commit_before>// Dynamic arenas.

export arena, arena_with_size;

import list;

type chunk = {data: [u8], mut fill: uint};
type arena = {mut chunks: list::list<@chunk>};

fn chunk(size: uint) -> @chunk {
    @{ data: vec::from_elem(size, 0u8), mut fill: 0u }
}

fn arena_with_size(initial_size: uint) -> arena {
    ret {mut chunks: list::cons(chunk(initial_size), @list::nil)};
}

fn arena() -> arena {
    arena_with_size(32u)
}

impl arena for arena {
    fn alloc(n_bytes: uint, align: uint) -> *() {
        let alignm1 = align - 1u;
        let mut head = list::head(self.chunks);

        let mut start = head.fill;
        start = (start + alignm1) & !alignm1;
        let mut end = start + n_bytes;

        if end > vec::len(head.data) {
            // Allocate a new chunk.
            let new_min_chunk_size = uint::max(n_bytes, vec::len(head.data));
            head = chunk(uint::next_power_of_two(new_min_chunk_size));
            self.chunks = list::cons(head, @self.chunks);
            start = 0u;
            end = n_bytes;
        }

        let p = ptr::offset(ptr::addr_of(head.fill), start);
        head.fill = end;
        unsafe { ret unsafe::reinterpret_cast(p); }
    }
}

<commit_msg>stdlib: Fix a pointer mistake in arenas<commit_after>// Dynamic arenas.

export arena, arena_with_size;

import list;

type chunk = {data: [u8], mut fill: uint};
type arena = {mut chunks: list::list<@chunk>};

fn chunk(size: uint) -> @chunk {
    @{ data: vec::from_elem(size, 0u8), mut fill: 0u }
}

fn arena_with_size(initial_size: uint) -> arena {
    ret {mut chunks: list::cons(chunk(initial_size), @list::nil)};
}

fn arena() -> arena {
    arena_with_size(32u)
}

impl arena for arena {
    fn alloc(n_bytes: uint, align: uint) -> *() {
        let alignm1 = align - 1u;
        let mut head = list::head(self.chunks);

        let mut start = head.fill;
        start = (start + alignm1) & !alignm1;
        let mut end = start + n_bytes;

        if end > vec::len(head.data) {
            // Allocate a new chunk.
            let new_min_chunk_size = uint::max(n_bytes, vec::len(head.data));
            head = chunk(uint::next_power_of_two(new_min_chunk_size));
            self.chunks = list::cons(head, @self.chunks);
            start = 0u;
            end = n_bytes;
        }

        unsafe {
            let p = ptr::offset(vec::unsafe::to_ptr(head.data), start);
            head.fill = end;
            ret unsafe::reinterpret_cast(p);
        }
    }
}

<|endoftext|>


<commit_before>// Copyright 2015 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.

extern crate gcc;
extern crate build_helper;

use std::env;
use std::fs;
use std::path::PathBuf;
use std::process::Command;

use build_helper::run;

fn main() {
    println!("cargo:rustc-cfg=cargobuild");

    let target = env::var("TARGET").unwrap();
    let host = env::var("HOST").unwrap();
    if !target.contains("apple") && !target.contains("msvc") && !target.contains("emscripten"){
        build_libbacktrace(&host, &target);
    }

    if target.contains("unknown-linux") {
        if target.contains("musl") && (target.contains("x86_64") || target.contains("i686")) {
            println!("cargo:rustc-link-lib=static=unwind");
        } else {
            println!("cargo:rustc-link-lib=dl");
            println!("cargo:rustc-link-lib=rt");
            println!("cargo:rustc-link-lib=pthread");
            println!("cargo:rustc-link-lib=gcc_s");
        }
    } else if target.contains("android") {
        println!("cargo:rustc-link-lib=dl");
        println!("cargo:rustc-link-lib=log");
        println!("cargo:rustc-link-lib=gcc");
    } else if target.contains("freebsd") {
        println!("cargo:rustc-link-lib=execinfo");
        println!("cargo:rustc-link-lib=pthread");
        println!("cargo:rustc-link-lib=gcc_s");
    } else if target.contains("dragonfly") || target.contains("bitrig") ||
              target.contains("netbsd") || target.contains("openbsd") {
        println!("cargo:rustc-link-lib=pthread");

        if target.contains("rumprun") {
            println!("cargo:rustc-link-lib=unwind");
        } else if target.contains("netbsd") || target.contains("openbsd") {
            println!("cargo:rustc-link-lib=gcc");
        } else if target.contains("bitrig") {
            println!("cargo:rustc-link-lib=c++abi");
        } else if target.contains("dragonfly") {
            println!("cargo:rustc-link-lib=gcc_pic");
        }
    } else if target.contains("apple-darwin") {
        println!("cargo:rustc-link-lib=System");
    } else if target.contains("apple-ios") {
        println!("cargo:rustc-link-lib=System");
        println!("cargo:rustc-link-lib=objc");
        println!("cargo:rustc-link-lib=framework=Security");
        println!("cargo:rustc-link-lib=framework=Foundation");
    } else if target.contains("windows") {
        if target.contains("windows-gnu") {
            println!("cargo:rustc-link-lib=gcc_eh");
        }
        println!("cargo:rustc-link-lib=advapi32");
        println!("cargo:rustc-link-lib=ws2_32");
        println!("cargo:rustc-link-lib=userenv");
        println!("cargo:rustc-link-lib=shell32");
    }
}

fn build_libbacktrace(host: &str, target: &str) {
    let src_dir = env::current_dir().unwrap().join("../libbacktrace");
    let build_dir = PathBuf::from(env::var_os("OUT_DIR").unwrap());

    println!("cargo:rustc-link-lib=static=backtrace");
    println!("cargo:rustc-link-search=native={}/.libs", build_dir.display());

    if fs::metadata(&build_dir.join(".libs/libbacktrace.a")).is_ok() {
        return
    }

    let compiler = gcc::Config::new().get_compiler();
    let ar = build_helper::cc2ar(compiler.path(), target);
    let cflags = compiler.args().iter().map(|s| s.to_str().unwrap())
                         .collect::<Vec<_>>().join(" ");
    run(Command::new("sh")
                .current_dir(&build_dir)
                .arg(src_dir.join("configure").to_str().unwrap()
                            .replace("C:\\", "/c/")
                            .replace("\\", "/"))
                .arg("--with-pic")
                .arg("--disable-multilib")
                .arg("--disable-shared")
                .arg("--disable-host-shared")
                .arg(format!("--host={}", build_helper::gnu_target(target)))
                .arg(format!("--build={}", build_helper::gnu_target(host)))
                .env("CC", compiler.path())
                .env("AR", &ar)
                .env("RANLIB", format!("{} s", ar.display()))
                .env("CFLAGS", cflags));
    run(Command::new("make")
                .current_dir(&build_dir)
                .arg(format!("INCDIR={}", src_dir.display()))
                .arg("-j").arg(env::var("NUM_JOBS").unwrap()));
}
<commit_msg>cover more linux targets in libstd cargobuild<commit_after>// Copyright 2015 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.

extern crate gcc;
extern crate build_helper;

use std::env;
use std::fs;
use std::path::PathBuf;
use std::process::Command;

use build_helper::run;

fn main() {
    println!("cargo:rustc-cfg=cargobuild");

    let target = env::var("TARGET").unwrap();
    let host = env::var("HOST").unwrap();
    if !target.contains("apple") && !target.contains("msvc") && !target.contains("emscripten"){
        build_libbacktrace(&host, &target);
    }

    if target.contains("linux") {
        if target.contains("musl") && (target.contains("x86_64") || target.contains("i686")) {
            println!("cargo:rustc-link-lib=static=unwind");
        } else if target.contains("android") {
            println!("cargo:rustc-link-lib=dl");
            println!("cargo:rustc-link-lib=log");
            println!("cargo:rustc-link-lib=gcc");
        } else {
            println!("cargo:rustc-link-lib=dl");
            println!("cargo:rustc-link-lib=rt");
            println!("cargo:rustc-link-lib=pthread");
            println!("cargo:rustc-link-lib=gcc_s");
        }
    } else if target.contains("freebsd") {
        println!("cargo:rustc-link-lib=execinfo");
        println!("cargo:rustc-link-lib=pthread");
        println!("cargo:rustc-link-lib=gcc_s");
    } else if target.contains("dragonfly") || target.contains("bitrig") ||
              target.contains("netbsd") || target.contains("openbsd") {
        println!("cargo:rustc-link-lib=pthread");

        if target.contains("rumprun") {
            println!("cargo:rustc-link-lib=unwind");
        } else if target.contains("netbsd") || target.contains("openbsd") {
            println!("cargo:rustc-link-lib=gcc");
        } else if target.contains("bitrig") {
            println!("cargo:rustc-link-lib=c++abi");
        } else if target.contains("dragonfly") {
            println!("cargo:rustc-link-lib=gcc_pic");
        }
    } else if target.contains("apple-darwin") {
        println!("cargo:rustc-link-lib=System");
    } else if target.contains("apple-ios") {
        println!("cargo:rustc-link-lib=System");
        println!("cargo:rustc-link-lib=objc");
        println!("cargo:rustc-link-lib=framework=Security");
        println!("cargo:rustc-link-lib=framework=Foundation");
    } else if target.contains("windows") {
        if target.contains("windows-gnu") {
            println!("cargo:rustc-link-lib=gcc_eh");
        }
        println!("cargo:rustc-link-lib=advapi32");
        println!("cargo:rustc-link-lib=ws2_32");
        println!("cargo:rustc-link-lib=userenv");
        println!("cargo:rustc-link-lib=shell32");
    }
}

fn build_libbacktrace(host: &str, target: &str) {
    let src_dir = env::current_dir().unwrap().join("../libbacktrace");
    let build_dir = PathBuf::from(env::var_os("OUT_DIR").unwrap());

    println!("cargo:rustc-link-lib=static=backtrace");
    println!("cargo:rustc-link-search=native={}/.libs", build_dir.display());

    if fs::metadata(&build_dir.join(".libs/libbacktrace.a")).is_ok() {
        return
    }

    let compiler = gcc::Config::new().get_compiler();
    let ar = build_helper::cc2ar(compiler.path(), target);
    let cflags = compiler.args().iter().map(|s| s.to_str().unwrap())
                         .collect::<Vec<_>>().join(" ");
    run(Command::new("sh")
                .current_dir(&build_dir)
                .arg(src_dir.join("configure").to_str().unwrap()
                            .replace("C:\\", "/c/")
                            .replace("\\", "/"))
                .arg("--with-pic")
                .arg("--disable-multilib")
                .arg("--disable-shared")
                .arg("--disable-host-shared")
                .arg(format!("--host={}", build_helper::gnu_target(target)))
                .arg(format!("--build={}", build_helper::gnu_target(host)))
                .env("CC", compiler.path())
                .env("AR", &ar)
                .env("RANLIB", format!("{} s", ar.display()))
                .env("CFLAGS", cflags));
    run(Command::new("make")
                .current_dir(&build_dir)
                .arg(format!("INCDIR={}", src_dir.display()))
                .arg("-j").arg(env::var("NUM_JOBS").unwrap()));
}
<|endoftext|>


<commit_before><commit_msg>Hacking up a storage subsystem design<commit_after>// "Tifflin" Kernel
// - By John Hodge (thePowersGang)
//
// Core/metadevs/storage.rs
// - Storage (block device) subsystem
module_define!(Storage, [], init)

/// A unique handle to a storage volume (logical)
pub struct VolumeHandle
{
	lv_idx: uint,
}

/// Physical volume instance provided by driver
pub trait PhysicalVolume
{
	fn name(&self) -> &str;	// Local lifetime string
	fn blocksize(&self) -> uint;	// Must return a power of two
	fn capacity(&self) -> u64;
	fn read(&self, prio: uint, blockidx: u64, count: uint, dst: &mut [u8]) -> bool;
	fn write(&mut self, prio: uint, blockidx: u64, count: uint, src: &[u8]) -> bool;
	fn wipe(&mut self, blockidx: u64, count: uint);
}

/// Registration for a physical volume handling driver
trait Mapper
{
	fn name(&self) -> &str;
	fn handles_pv(&self, pv: &PhysicalVolume) -> uint;
}

/// A single logical volume, composed of 1 or more physical blocks
struct LogicalVolume
{
	block_size: uint,	///< Logical block size (max physical block size)
	region_size: Option<uint>,	///< Number of bytes in each physical region, None = JBOD
	regions: Vec<PhysicalRegion>,
}
/// Physical region used by a logical volume
struct PhysicalRegion
{
	volume: uint,
	block_count: uint,	// uint to save space in average case
	first_block: u64,
}

static s_next_pv_idx: AtomicUInt = ATOMIC_UINT_INIT;
static s_physical_volumes: Mutex<HashMap<uint,Box<PhysicalVolume+Send>>> = mutex_init!( hashmap_init!() );
static s_logical_volumes: Mutex<HashMap<uint,LogicalVolume>> = mutex_init!( hashmap_init!() );
static s_mappers: Mutex<Vec<&'static Mapper+Send> = mutex_init!( vec_init!() );

// TODO: Maintain a set of registered volumes. Mappers can bind onto a volume and register new LVs
// TODO: Maintain set of active mappings (set of PVs -> set of LVs)
// NOTE: Should unbinding of LVs be allowed? (Yes, for volume removal)

fn init()
{
}

pub fn register_pv(pv: Box<PhysicalVolume+Send>) -> PhysicalVolumeReg
{
	let pv_id = s_next_pv_idx.inc();
	s_physical_volumes.lock().set(pv_id, pv)

	// Now that a new PV has been inserted, handlers should be informed
	let mut best_mapper = None;
	let mut best_mapper_level = 0;
	let mappers = s_mappers.lock();
	for mapper in mappers.iter()
	{
		let level = mapper.handles_pv(&*pv);
		if level == 0
		{
		}
		else if level < best_mapper_level
		{
		}
		else if level == best_mapper_level
		{
			// Fight!
			log_warning!("LV Mappers {} and {} are fighting over {}",
				mapper.name(), best_mapper.unwrap().name(), pv.name());
		}
		else
		{
			best_mapper = Some(mapper);
			best_mapper_level = level;
		}
	}
	if let Some(mapper) = best_mapper
	{
		// Poke mapper
	}
	PhysicalVolumeReg { idx: pv_id }
}

/// Function called when a new volume is registered (physical or logical)
fn new_volume(volidx: uint)
{
}

pub fn enum_pvs() -> Vec<(uint,String)>
{
	s_physical_volumes.lock().iter().map(|k,v| (*k, String::new(*v)) ).collect()
}

// vim: ft=rust
<|endoftext|>


<commit_before>// Copyright 2012 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.

extern mod std;
use std::map;
use std::map::HashMap;
use std::map::StdMap;

// Test that trait types printed in error msgs include the type arguments.

fn main() {
    let x: StdMap<~str,~str> = map::HashMap::<~str,~str>() as
        StdMap::<~str,~str>;
    let y: StdMap<uint,~str> = x;
    //~^ ERROR mismatched types: expected `@std::map::StdMap<uint,~str>`
}
<commit_msg>update compile-fail/map-types.rs to use hashmap<commit_after>// Copyright 2012 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.

use core::container::Map;
use core::hashmap::linear::LinearMap;

// Test that trait types printed in error msgs include the type arguments.

fn main() {
    let x: Map<~str, ~str> = LinearMap::new::<~str, ~str>() as
        Map::<~str, ~str>;
    let y: Map<uint, ~str> = x;
    //~^ ERROR mismatched types: expected `@core::container::Map/&<uint,~str>`
}
<|endoftext|>


<commit_before>use sys::size_of;
extern mod std;

struct Cat {
    x: int
}

struct Kitty {
    x: int,
    drop {}
}

fn main() {
    assert (size_of::<Cat>() == 8 as uint);
    assert (size_of::<Kitty>() == 16 as uint);
}
<commit_msg>Fix run-pass/issue-2895 for 32-bit archs<commit_after>use sys::size_of;
extern mod std;

struct Cat {
    x: int
}

struct Kitty {
    x: int,
    drop {}
}

#[cfg(target_arch = "x86_64")]
fn main() {
    assert (size_of::<Cat>() == 8 as uint);
    assert (size_of::<Kitty>() == 16 as uint);
}

#[cfg(target_arch = "x86")]
fn main() {
    assert (size_of::<Cat>() == 4 as uint);
    assert (size_of::<Kitty>() == 8 as uint);
}
<|endoftext|>


<commit_before><commit_msg>Made table output nicer<commit_after><|endoftext|>


<commit_before><commit_msg>????????<commit_after><|endoftext|>


<commit_before>use std::sync::atomic::Ordering::{Acquire, Release, Relaxed};
use std::{ptr, mem};

use mem::epoch::{self, Atomic, Owned};
use mem::CachePadded;

/// A Michael-Scott lock-free queue.
///
/// Usable with any number of producers and consumers.
pub struct MsQueue<T> {
    head: CachePadded<Atomic<Node<T>>>,
    tail: CachePadded<Atomic<Node<T>>>,
}

struct Node<T> {
    data: T,
    next: Atomic<Node<T>>,
}

impl<T> MsQueue<T> {
    /// Create a new, empty queue.
    pub fn new() -> MsQueue<T> {
        let q = MsQueue {
            head: CachePadded::new(Atomic::null()),
            tail: CachePadded::new(Atomic::null()),
        };
        let sentinel = Owned::new(Node {
            data: unsafe { mem::uninitialized() },
            next: Atomic::null()
        });
        let guard = epoch::pin();
        let sentinel = q.head.store_and_ref(sentinel, Relaxed, &guard);
        q.tail.store_shared(Some(sentinel), Relaxed);
        q
    }

    /// Add `t` to the back of the queue.
    pub fn push(&self, t: T) {
        let mut n = Owned::new(Node {
            data: t,
            next: Atomic::null()
        });
        let guard = epoch::pin();
        loop {
            let tail = self.tail.load(Acquire, &guard).unwrap();
            if let Some(next) = tail.next.load(Relaxed, &guard) {
                self.tail.cas_shared(Some(tail), Some(next), Relaxed);
                continue;
            }

            match tail.next.cas_and_ref(None, n, Release, &guard) {
                Ok(shared) => {
                    self.tail.cas_shared(Some(tail), Some(shared), Relaxed);
                    break;
                }
                Err(owned) => {
                    n = owned;
                }
            }
        }
    }

    /// Attempt to dequeue from the front.
    ///
    /// Returns `None` if the queue is observed to be empty.
    pub fn pop(&self) -> Option<T> {
        let guard = epoch::pin();
        loop {
            let head = self.head.load(Acquire, &guard).unwrap();

            if let Some(next) = head.next.load(Relaxed, &guard) {
                unsafe {
                    if self.head.cas_shared(Some(head), Some(next), Relaxed) {
                        guard.unlinked(head);
                        return Some(ptr::read(&(*next).data))
                    }
                }
            } else {
                return None
            }
        }
    }
}

#[cfg(test)]
mod test {
    const CONC_COUNT: i64 = 1000000;

    use std::io::stderr;
    use std::io::prelude::*;

    use mem::epoch;
    use scope;
    use super::*;

    #[test]
    fn smoke_queue() {
        let q: MsQueue<i64> = MsQueue::new();
    }

    #[test]
    fn push_pop_1() {
        let q: MsQueue<i64> = MsQueue::new();
        q.push(37);
        assert_eq!(q.pop(), Some(37));
    }

    #[test]
    fn push_pop_2() {
        let q: MsQueue<i64> = MsQueue::new();
        q.push(37);
        q.push(48);
        assert_eq!(q.pop(), Some(37));
        assert_eq!(q.pop(), Some(48));
    }

    #[test]
    fn push_pop_many_seq() {
        let q: MsQueue<i64> = MsQueue::new();
        for i in 0..200 {
            q.push(i)
        }
        for i in 0..200 {
            assert_eq!(q.pop(), Some(i));
        }
    }

    #[test]
    fn push_pop_many_spsc() {
        let q: MsQueue<i64> = MsQueue::new();

        scope(|scope| {
            scope.spawn(|| {
                let mut next = 0;

                while next < CONC_COUNT {
                    if let Some(elem) = q.pop() {
                        assert_eq!(elem, next);
                        next += 1;
                    }
                }
            });

            for i in 0..CONC_COUNT {
                q.push(i)
            }
        });
    }

    #[test]
    fn push_pop_many_spmc() {
        use std::time::Duration;

        fn recv(t: i32, q: &MsQueue<i64>) {
            let mut cur = -1;
            for i in 0..CONC_COUNT {
                if let Some(elem) = q.pop() {
                    if elem <= cur {
                        writeln!(stderr(), "{}: {} <= {}", t, elem, cur);
                    }
                    assert!(elem > cur);
                    cur = elem;

                    if cur == CONC_COUNT - 1 { break }
                }

                if i % 10000 == 0 {
                    //writeln!(stderr(), "{}: {} @ {}", t, i, cur);
                }
            }
        }

        let q: MsQueue<i64> = MsQueue::new();
        let qr = &q;
        scope(|scope| {
            for i in 0..3 {
                scope.spawn(move || recv(i, qr));
            }

            scope.spawn(|| {
                for i in 0..CONC_COUNT {
                    q.push(i);

                    if i % 10000 == 0 {
                        //writeln!(stderr(), "Push: {}", i);
                    }
                }
            })
        });
    }

    #[test]
    fn push_pop_many_mpmc() {
        enum LR { Left(i64), Right(i64) }

        let q: MsQueue<LR> = MsQueue::new();

        scope(|scope| {
            for _t in 0..2 {
                scope.spawn(|| {
                    for i in CONC_COUNT-1..CONC_COUNT {
                        q.push(LR::Left(i))
                    }
                });
                scope.spawn(|| {
                    for i in CONC_COUNT-1..CONC_COUNT {
                        q.push(LR::Right(i))
                    }
                });
                scope.spawn(|| {
                    let mut vl = vec![];
                    let mut vr = vec![];
                    for _i in 0..CONC_COUNT {
                        match q.pop() {
                            Some(LR::Left(x)) => vl.push(x),
                            Some(LR::Right(x)) => vr.push(x),
                            _ => {}
                        }
                    }

                    let mut vl2 = vl.clone();
                    let mut vr2 = vr.clone();
                    vl2.sort();
                    vr2.sort();

                    assert_eq!(vl, vl2);
                    assert_eq!(vr, vr2);
                });
            }
        });
    }
}
<commit_msg>Fix memory ordering on MsQueue<commit_after>use std::sync::atomic::Ordering::{Acquire, Release, Relaxed};
use std::{ptr, mem};

use mem::epoch::{self, Atomic, Owned};
use mem::CachePadded;

/// A Michael-Scott lock-free queue.
///
/// Usable with any number of producers and consumers.
pub struct MsQueue<T> {
    head: CachePadded<Atomic<Node<T>>>,
    tail: CachePadded<Atomic<Node<T>>>,
}

struct Node<T> {
    data: T,
    next: Atomic<Node<T>>,
}

impl<T> MsQueue<T> {
    /// Create a new, empty queue.
    pub fn new() -> MsQueue<T> {
        let q = MsQueue {
            head: CachePadded::new(Atomic::null()),
            tail: CachePadded::new(Atomic::null()),
        };
        let sentinel = Owned::new(Node {
            data: unsafe { mem::uninitialized() },
            next: Atomic::null()
        });
        let guard = epoch::pin();
        let sentinel = q.head.store_and_ref(sentinel, Relaxed, &guard);
        q.tail.store_shared(Some(sentinel), Relaxed);
        q
    }

    /// Add `t` to the back of the queue.
    pub fn push(&self, t: T) {
        let mut n = Owned::new(Node {
            data: t,
            next: Atomic::null()
        });
        let guard = epoch::pin();
        loop {
            let tail = self.tail.load(Acquire, &guard).unwrap();
            if let Some(next) = tail.next.load(Acquire, &guard) {
                self.tail.cas_shared(Some(tail), Some(next), Release);
                continue;
            }

            match tail.next.cas_and_ref(None, n, Release, &guard) {
                Ok(shared) => {
                    self.tail.cas_shared(Some(tail), Some(shared), Release);
                    break;
                }
                Err(owned) => {
                    n = owned;
                }
            }
        }
    }

    /// Attempt to dequeue from the front.
    ///
    /// Returns `None` if the queue is observed to be empty.
    pub fn pop(&self) -> Option<T> {
        let guard = epoch::pin();
        loop {
            let head = self.head.load(Acquire, &guard).unwrap();

            if let Some(next) = head.next.load(Acquire, &guard) {
                unsafe {
                    if self.head.cas_shared(Some(head), Some(next), Release) {
                        guard.unlinked(head);
                        return Some(ptr::read(&(*next).data))
                    }
                }
            } else {
                return None
            }
        }
    }
}

#[cfg(test)]
mod test {
    const CONC_COUNT: i64 = 1000000;

    use std::io::stderr;
    use std::io::prelude::*;

    use mem::epoch;
    use scope;
    use super::*;

    #[test]
    fn smoke_queue() {
        let q: MsQueue<i64> = MsQueue::new();
    }

    #[test]
    fn push_pop_1() {
        let q: MsQueue<i64> = MsQueue::new();
        q.push(37);
        assert_eq!(q.pop(), Some(37));
    }

    #[test]
    fn push_pop_2() {
        let q: MsQueue<i64> = MsQueue::new();
        q.push(37);
        q.push(48);
        assert_eq!(q.pop(), Some(37));
        assert_eq!(q.pop(), Some(48));
    }

    #[test]
    fn push_pop_many_seq() {
        let q: MsQueue<i64> = MsQueue::new();
        for i in 0..200 {
            q.push(i)
        }
        for i in 0..200 {
            assert_eq!(q.pop(), Some(i));
        }
    }

    #[test]
    fn push_pop_many_spsc() {
        let q: MsQueue<i64> = MsQueue::new();

        scope(|scope| {
            scope.spawn(|| {
                let mut next = 0;

                while next < CONC_COUNT {
                    if let Some(elem) = q.pop() {
                        assert_eq!(elem, next);
                        next += 1;
                    }
                }
            });

            for i in 0..CONC_COUNT {
                q.push(i)
            }
        });
    }

    #[test]
    fn push_pop_many_spmc() {
        use std::time::Duration;

        fn recv(t: i32, q: &MsQueue<i64>) {
            let mut cur = -1;
            for i in 0..CONC_COUNT {
                if let Some(elem) = q.pop() {
                    if elem <= cur {
                        writeln!(stderr(), "{}: {} <= {}", t, elem, cur);
                    }
                    assert!(elem > cur);
                    cur = elem;

                    if cur == CONC_COUNT - 1 { break }
                }

                if i % 10000 == 0 {
                    //writeln!(stderr(), "{}: {} @ {}", t, i, cur);
                }
            }
        }

        let q: MsQueue<i64> = MsQueue::new();
        let qr = &q;
        scope(|scope| {
            for i in 0..3 {
                scope.spawn(move || recv(i, qr));
            }

            scope.spawn(|| {
                for i in 0..CONC_COUNT {
                    q.push(i);

                    if i % 10000 == 0 {
                        //writeln!(stderr(), "Push: {}", i);
                    }
                }
            })
        });
    }

    #[test]
    fn push_pop_many_mpmc() {
        enum LR { Left(i64), Right(i64) }

        let q: MsQueue<LR> = MsQueue::new();

        scope(|scope| {
            for _t in 0..2 {
                scope.spawn(|| {
                    for i in CONC_COUNT-1..CONC_COUNT {
                        q.push(LR::Left(i))
                    }
                });
                scope.spawn(|| {
                    for i in CONC_COUNT-1..CONC_COUNT {
                        q.push(LR::Right(i))
                    }
                });
                scope.spawn(|| {
                    let mut vl = vec![];
                    let mut vr = vec![];
                    for _i in 0..CONC_COUNT {
                        match q.pop() {
                            Some(LR::Left(x)) => vl.push(x),
                            Some(LR::Right(x)) => vr.push(x),
                            _ => {}
                        }
                    }

                    let mut vl2 = vl.clone();
                    let mut vr2 = vr.clone();
                    vl2.sort();
                    vr2.sort();

                    assert_eq!(vl, vl2);
                    assert_eq!(vr, vr2);
                });
            }
        });
    }
}
<|endoftext|>


<commit_before><commit_msg>The object in `let if` is dropped after else statement<commit_after>use std::ops::Drop;

struct A;
impl Drop for A {
    fn drop(&mut self) {
        println!("drop");
    }
}

enum E {
    A(A),
    B(A),
}

fn main() {
    println!("start");
    if let E::B(a) = E::A(A{}) {
        println!("if");
    } else {
        println!("else");
    }
    println!("fin");
}
<|endoftext|>


<commit_before>use super::*;

impl Editor {
    /// Go to next char
    pub fn next(&mut self) {
        if self.x() == self.text[self.y()].len() {
            if self.y() >= self.text.len() {
                self.text.push_back(VecDeque::new())
            }
            if self.y() < self.text.len() - 1 {
                self.cursor_mut().x = 0;
                self.cursor_mut().y += 1;
            }

        } else {
            self.cursor_mut().x += 1;
        }
    }

    /// Go to previous char
    pub fn previous(&mut self) {
        if self.x() == 0 {
            if self.y() > 0 {
                self.cursor_mut().y -= 1;
                self.cursor_mut().x = self.text[self.y() - 1].len();
            }
        } else {
            self.cursor_mut().y -= 1;
        }

    }

    /// Go right
    pub fn right(&mut self, n: usize) {
        let x = self.x() + n;
        let y = self.y();

        let text = self.text.clone();
        let curs = self.cursor_mut();

        curs.x += n;

        if x > text[y].len() {
            curs.x = text[y].len();
        }
    }
    /// Go left
    pub fn left(&mut self, n: usize) {
        let x = self.x();
        let y = self.y();

        let text = self.text.clone();
        let curs = self.cursor_mut();

        if n <= x {
            curs.x -= n;
        } else {
            curs.x = 0;
        }

    }
    /// Go up
    pub fn up(&mut self, n: usize) {
        let y = self.y();
        let curs = self.cursor_mut();
        if n <= y {
            curs.y -= n;
        } else {
            curs.y = 0;
        }
    }
    /// Go down
    pub fn down(&mut self, n: usize) {
        let x = self.x();
        let y = self.y() + n;

        let text = self.text.clone();
        let curs = self.cursor_mut();

        curs.y += n;

        if y >= text.len() {
            curs.y = text.len() - 1;
        }
    }
}
<commit_msg>Fix movement<commit_after>use super::*;

impl Editor {
    /// Go to next char
    pub fn next(&mut self) {
        if self.x() == self.text[self.y()].len() {
            if self.y() >= self.text.len() {
                self.text.push_back(VecDeque::new())
            }
            if self.y() < self.text.len() - 1 {
                self.cursor_mut().x = 0;
                self.cursor_mut().y += 1;
            }

        } else {
            self.cursor_mut().x += 1;
        }
    }

    /// Go to previous char
    pub fn previous(&mut self) {
        if self.x() == 0 {
            if self.y() > 0 {
                self.cursor_mut().y -= 1;
                self.cursor_mut().x = self.text[self.y() - 1].len();
            }
        } else {
            self.cursor_mut().y -= 1;
        }

    }

    /// Go right
    pub fn right(&mut self, n: usize) {
        let x = self.x() + n;
        let y = self.y();

        let text = self.text.clone();
        let curs = self.cursor_mut();

        curs.x += n;

        if x > text[y].len() {
            curs.x = text[y].len();
        }
    }
    /// Go left
    pub fn left(&mut self, n: usize) {
        let x = self.x();
        let y = self.y();

        let text = self.text.clone();
        let curs = self.cursor_mut();

        if n <= x {
            curs.x = x - n;
        } else {
            curs.x = 0;
        }

    }
    /// Go up
    pub fn up(&mut self, n: usize) {
        let y = self.y();
        let curs = self.cursor_mut();
        if n <= y {
            curs.y -= n;
        } else {
            curs.y = 0;
        }
    }
    /// Go down
    pub fn down(&mut self, n: usize) {
        let x = self.x();
        let y = self.y() + n;

        let text = self.text.clone();
        let curs = self.cursor_mut();

        curs.y += n;

        if y >= text.len() {
            curs.y = text.len() - 1;
        }
    }
}
<|endoftext|>


<commit_before><commit_msg>Hack up initial Rust support for RMC!<commit_after>use std::sync::atomic::{Ordering, AtomicUsize};

////////////////////
extern {
    fn __rmc_action_register(name: *const u8) -> i32;
    fn __rmc_action_close(reg_id: i32) -> i32;
    fn __rmc_edge_register(is_vis: i32, src: *const u8, dst: *const u8) -> i32;
    fn __rmc_push() -> i32;
}

macro_rules! ident_cstr {
    ($i:ident) => { concat!(stringify!($i), "\0").as_ptr() }
}

macro_rules! L {
    ($label:ident, $e:expr) => {{
        let id = __rmc_action_register(ident_cstr!($label));
        let v = $e;
        __rmc_action_close(id);
        v
    }}
}

macro_rules! PUSH { () => { __rmc_push() } }

macro_rules! RMC_EDGE {
    ($sort:expr, $src:ident, $dst:ident) => {
        __rmc_edge_register($sort, ident_cstr!($src), ident_cstr!($dst))
    }
}
macro_rules! XEDGE {
    ($src:ident, $dst:ident) => { RMC_EDGE!(0, $src, $dst) }
}
macro_rules! VEDGE {
    ($src:ident, $dst:ident) => { RMC_EDGE!(1, $src, $dst) }
}

/////////////////////////////////

pub unsafe fn mp_send_test(data: *mut AtomicUsize, flag: *mut AtomicUsize) {
    VEDGE!(wdata, wflag);
    L!(wdata, (*data).store(42, Ordering::Relaxed));
    L!(wflag, (*flag).store(1, Ordering::Relaxed));
}
<|endoftext|>


<commit_before><commit_msg>Add unixecho example<commit_after>extern crate mioco;
extern crate env_logger;

use std::io::{self, Read, Write};
use mioco::unix::UnixListener;

const DEFAULT_LISTEN_ADDR : &'static str = "/tmp/.unixecho.socket";

fn main() {
    env_logger::init().unwrap();

    mioco::start(|| -> io::Result<()> {
        let listener = try!(UnixListener::bind(DEFAULT_LISTEN_ADDR));

        println!("Starting unix echo server on {:?}", DEFAULT_LISTEN_ADDR);

        loop {
            let mut conn = try!(listener.accept());

            mioco::spawn(move || -> io::Result<()> {
                let mut buf = [0u8; 1024 * 16];
                loop {
                    let size = try!(conn.read(&mut buf));
                    if size == 0 {/* eof */ break; }
                    let _ = try!(conn.write_all(&mut buf[0..size]));
                }

                Ok(())
            });
        }
    }).unwrap().unwrap();
}
<|endoftext|>


<commit_before><commit_msg>Get basic functionality to work<commit_after>#[link(name="du", vers="1.0.0", author="Derek Chiang")];

/*
 * This file is part of the uutils coreutils package.
 *
 * (c) Derek Chiang <derekchiang93@gmail.com>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

extern mod extra;

use std::os;
use std::io::stderr;
use std::io::fs;
use std::io::FileStat;
use std::path::Path;
use std::uint;
use std::comm::{Port, Chan, SharedChan, stream};
use extra::arc::Arc;
use extra::future::Future;
use extra::getopts::groups;

static VERSION: &'static str = "1.0.0";

fn du(path: &Path) -> ~[Arc<FileStat>] {
    let mut stats = ~[];
    let mut futures = ~[];
    stats.push(Arc::new(path.stat()));

    for f in fs::readdir(path).move_iter() {
        match f.is_file() {
            true => stats.push(Arc::new(f.stat())),
            false => futures.push(do Future::spawn { du(&f) })
        }
    }

    for future in futures.mut_iter() {
        stats.push_all(future.get());
    }

    return stats;
}

fn main() {
    let args = os::args();
    let program = args[0].clone();
    let opts = ~[
        groups::optflag("a", "all", " write counts for all files, not just directories"),
        groups::optflag("", "apparent-size", "print apparent sizes,  rather  than  disk  usage;
            although  the apparent  size is usually smaller, it may be larger due to holes
            in ('sparse') files, internal  fragmentation,  indirect  blocks, and the like"),
        groups::optopt("B", "block-size", "scale sizes  by  SIZE before printing them.
            E.g., '-BM' prints sizes in units of 1,048,576 bytes.  See SIZE format below.",
            "SIZE"),
        groups::optflag("", "help", "display this help and exit"),
        groups::optflag("", "version", "output version information and exit"),
    ];

    let matches = match groups::getopts(args.tail(), opts) {
        Ok(m) => m,
        Err(f) => {
            writeln!(&mut stderr() as &mut Writer,
                "Invalid options\n{}", f.to_err_msg());
            os::set_exit_status(1);
            return
        }
    };

    if matches.opt_present("help") {
        println("du " + VERSION + " - estimate file space usage");
        println("");
        println("Usage:");
        println!("  {0:s} [OPTION]... [FILE]...", program);
        println!("  {0:s} [OPTION]... --files0-from=F", program);
        println("");
        println(groups::usage("Summarize disk usage of each FILE, recursively for directories.", opts));
        return;
    }

    if !matches.free.is_empty() {
    }

    let strs = match matches.free {
        [] => ~[~"./"],
        x => x
    };

    for path_str in strs.iter() {
        let path = Path::init(path_str.clone());
        for stat_arc in du(&path).move_iter() {
            let stat = stat_arc.get();
            println!("{:<10} {}", stat.size, stat.path.display());
        }
    }
}
<|endoftext|>


<commit_before><commit_msg>added iterator_find<commit_after>/*
pub trait Iterator {

    // `find` takes `&mut self` meaning the caller may be borrowed
    // and modified, but not consumed.
    fn find(&mut self, predicate: P) -> Option<Self::Item> where
        // `FnMut` meaning any captured variable may at most be
        // modified, not consumed. `&Self::Item` states it takes
        // arguments to the closure by reference.
        P: FnMut(&Self::Item) -> bool {}

}

*/

fn main() {

    let vec1 = vec![1,2,3];
    let vec2 = vec![4,8,9];

    println!("2 is present: {:?}", vec1.iter().find(|&&x| x==2));
    println!("2 is present: {:?}", vec2.into_iter().find(|&x| x==2));

    let arr1 = [1,2,3];
    let arr2 = [4,8,9];

    println!("2 is present: {:?}", arr1.into_iter().find(|&&x| x==2)); // still yields &&i32
    println!("2 is present: {:?}", arr2.iter().find(|&&x| x==2));

}<|endoftext|>


<commit_before><commit_msg>Add test for IntoIterator pattern blocked by #20220. Fixes #20220.<commit_after>// Copyright 2015 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.

// Test references to `Self::Item` in the trait. Issue #20220.

use std::vec;

trait IntoIteratorX {
    type Item;
    type IntoIter: Iterator<Item=Self::Item>;

    fn into_iter_x(self) -> Self::IntoIter;
}

impl<T> IntoIteratorX for Vec<T> {
    type Item = T;
    type IntoIter = vec::IntoIter<T>;

    fn into_iter_x(self) -> vec::IntoIter<T> {
        self.into_iter()
    }
}

fn main() {
    let vec = vec![1, 2, 3];
    for (i, e) in vec.into_iter().enumerate() {
        assert_eq!(i+1, e);
    }
}
<|endoftext|>


<commit_before>// Copyright 2012 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.

// Helper definition for test/run-pass/check-static-recursion-foreign.rs.

#![feature(libc)]

#[crate_id = "check_static_recursion_foreign_helper"]
#[crate_type = "lib"]

extern crate libc;

#[no_mangle]
pub static test_static: libc::c_int = 0;
<commit_msg>test - Add missing ! to crate_type/crate_id attributes<commit_after>// Copyright 2012 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.

// Helper definition for test/run-pass/check-static-recursion-foreign.rs.

#![feature(libc)]

#![crate_name = "check_static_recursion_foreign_helper"]
#![crate_type = "lib"]

extern crate libc;

#[no_mangle]
pub static test_static: libc::c_int = 0;
<|endoftext|>