nonzero.rs.html -- source
Description: Source to the Rust file `/usr/obj/ports/rust-1.16.0/rustc-1.16.0-src/src/libcore/nonzero.rs`.
Keywords: rust, rustlang, rust-lang

     1
     2
     3
     4
     5
     6
     7
     8
     9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    21
    22
    23
    24
    25
    26
    27
    28
    29
    30
    31
    32
    33
    34
    35
    36
    37
    38
    39
    40
    41
    42
    43
    44
    45
    46
    47
    48
    49
    50
    51
    52
    53
    54
    55
    56
    57
    58
    59
    60
    61
    62
    63

    // Copyright 2012-2014 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.

    //! Exposes the NonZero lang item which provides optimization hints.
    #![unstable(feature = "nonzero",
                reason = "needs an RFC to flesh out the design",
                issue = "27730")]

    use ops::{CoerceUnsized, Deref};

    /// Unsafe trait to indicate what types are usable with the NonZero struct
    pub unsafe trait Zeroable {}

    unsafe impl<T:?Sized> Zeroable for *const T {}
    unsafe impl<T:?Sized> Zeroable for *mut T {}
    unsafe impl Zeroable for isize {}
    unsafe impl Zeroable for usize {}
    unsafe impl Zeroable for i8 {}
    unsafe impl Zeroable for u8 {}
    unsafe impl Zeroable for i16 {}
    unsafe impl Zeroable for u16 {}
    unsafe impl Zeroable for i32 {}
    unsafe impl Zeroable for u32 {}
    unsafe impl Zeroable for i64 {}
    unsafe impl Zeroable for u64 {}
    #[cfg(not(stage0))]
    unsafe impl Zeroable for i128 {}
    #[cfg(not(stage0))]
    unsafe impl Zeroable for u128 {}

    /// A wrapper type for raw pointers and integers that will never be
    /// NULL or 0 that might allow certain optimizations.
    #[lang = "non_zero"]
    #[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Debug, Hash)]
    pub struct NonZero<T: Zeroable>(T);

    impl<T: Zeroable> NonZero<T> {
        /// Creates an instance of NonZero with the provided value.
        /// You must indeed ensure that the value is actually "non-zero".
        #[inline(always)]
        pub const unsafe fn new(inner: T) -> NonZero<T> {
            NonZero(inner)
        }
    }

    impl<T: Zeroable> Deref for NonZero<T> {
        type Target = T;

        #[inline]
        fn deref(&self) -> &T {
            let NonZero(ref inner) = *self;
            inner
        }
    }

    impl<T: Zeroable+CoerceUnsized<U>, U: Zeroable> CoerceUnsized<NonZero<U>> for NonZero<T> {}

# Help

## Keyboard Shortcuts

?
  Show this help dialog
S
  Focus the search field
⇤
  Move up in search results
⇥
  Move down in search results
⏎
  Go to active search result
+
  Collapse/expand all sections

## Search Tricks

Prefix searches with a type followed by a colon (e.g. `fn:`) to restrict the search to a given type.

Accepted types are: `fn`, `mod`, `struct`, `enum`, `trait`, `type`, `macro`, and `const`.

Search functions by type signature (e.g. `vec -> usize` or `* -> vec`)