mv std libs to library/
This commit is contained in:
mark
366
library/core/src/array/mod.rs
Normal file
366
library/core/src/array/mod.rs
Normal file
@@ -0,0 +1,366 @@
|
||||
//! Implementations of things like `Eq` for fixed-length arrays
|
||||
//! up to a certain length. Eventually, we should be able to generalize
|
||||
//! to all lengths.
|
||||
//!
|
||||
//! *[See also the array primitive type](../../std/primitive.array.html).*
|
||||
|
||||
#![stable(feature = "core_array", since = "1.36.0")]
|
||||
|
||||
use crate::borrow::{Borrow, BorrowMut};
|
||||
use crate::cmp::Ordering;
|
||||
use crate::convert::{Infallible, TryFrom};
|
||||
use crate::fmt;
|
||||
use crate::hash::{self, Hash};
|
||||
use crate::marker::Unsize;
|
||||
use crate::slice::{Iter, IterMut};
|
||||
|
||||
mod iter;
|
||||
|
||||
#[unstable(feature = "array_value_iter", issue = "65798")]
|
||||
pub use iter::IntoIter;
|
||||
|
||||
/// Utility trait implemented only on arrays of fixed size
|
||||
///
|
||||
/// This trait can be used to implement other traits on fixed-size arrays
|
||||
/// without causing much metadata bloat.
|
||||
///
|
||||
/// The trait is marked unsafe in order to restrict implementors to fixed-size
|
||||
/// arrays. User of this trait can assume that implementors have the exact
|
||||
/// layout in memory of a fixed size array (for example, for unsafe
|
||||
/// initialization).
|
||||
///
|
||||
/// Note that the traits [`AsRef`] and [`AsMut`] provide similar methods for types that
|
||||
/// may not be fixed-size arrays. Implementors should prefer those traits
|
||||
/// instead.
|
||||
///
|
||||
/// [`AsRef`]: ../convert/trait.AsRef.html
|
||||
/// [`AsMut`]: ../convert/trait.AsMut.html
|
||||
#[unstable(feature = "fixed_size_array", issue = "27778")]
|
||||
pub unsafe trait FixedSizeArray<T> {
|
||||
/// Converts the array to immutable slice
|
||||
#[unstable(feature = "fixed_size_array", issue = "27778")]
|
||||
fn as_slice(&self) -> &[T];
|
||||
/// Converts the array to mutable slice
|
||||
#[unstable(feature = "fixed_size_array", issue = "27778")]
|
||||
fn as_mut_slice(&mut self) -> &mut [T];
|
||||
}
|
||||
|
||||
#[unstable(feature = "fixed_size_array", issue = "27778")]
|
||||
unsafe impl<T, A: Unsize<[T]>> FixedSizeArray<T> for A {
|
||||
#[inline]
|
||||
fn as_slice(&self) -> &[T] {
|
||||
self
|
||||
}
|
||||
#[inline]
|
||||
fn as_mut_slice(&mut self) -> &mut [T] {
|
||||
self
|
||||
}
|
||||
}
|
||||
|
||||
/// The error type returned when a conversion from a slice to an array fails.
|
||||
#[stable(feature = "try_from", since = "1.34.0")]
|
||||
#[derive(Debug, Copy, Clone)]
|
||||
pub struct TryFromSliceError(());
|
||||
|
||||
#[stable(feature = "core_array", since = "1.36.0")]
|
||||
impl fmt::Display for TryFromSliceError {
|
||||
#[inline]
|
||||
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
|
||||
fmt::Display::fmt(self.__description(), f)
|
||||
}
|
||||
}
|
||||
|
||||
impl TryFromSliceError {
|
||||
#[unstable(
|
||||
feature = "array_error_internals",
|
||||
reason = "available through Error trait and this method should not \
|
||||
be exposed publicly",
|
||||
issue = "none"
|
||||
)]
|
||||
#[inline]
|
||||
#[doc(hidden)]
|
||||
pub fn __description(&self) -> &str {
|
||||
"could not convert slice to array"
|
||||
}
|
||||
}
|
||||
|
||||
#[stable(feature = "try_from_slice_error", since = "1.36.0")]
|
||||
impl From<Infallible> for TryFromSliceError {
|
||||
fn from(x: Infallible) -> TryFromSliceError {
|
||||
match x {}
|
||||
}
|
||||
}
|
||||
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
impl<T, const N: usize> AsRef<[T]> for [T; N] {
|
||||
#[inline]
|
||||
fn as_ref(&self) -> &[T] {
|
||||
&self[..]
|
||||
}
|
||||
}
|
||||
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
impl<T, const N: usize> AsMut<[T]> for [T; N] {
|
||||
#[inline]
|
||||
fn as_mut(&mut self) -> &mut [T] {
|
||||
&mut self[..]
|
||||
}
|
||||
}
|
||||
|
||||
#[stable(feature = "array_borrow", since = "1.4.0")]
|
||||
impl<T, const N: usize> Borrow<[T]> for [T; N] {
|
||||
fn borrow(&self) -> &[T] {
|
||||
self
|
||||
}
|
||||
}
|
||||
|
||||
#[stable(feature = "array_borrow", since = "1.4.0")]
|
||||
impl<T, const N: usize> BorrowMut<[T]> for [T; N] {
|
||||
fn borrow_mut(&mut self) -> &mut [T] {
|
||||
self
|
||||
}
|
||||
}
|
||||
|
||||
#[stable(feature = "try_from", since = "1.34.0")]
|
||||
impl<T, const N: usize> TryFrom<&[T]> for [T; N]
|
||||
where
|
||||
T: Copy,
|
||||
{
|
||||
type Error = TryFromSliceError;
|
||||
|
||||
fn try_from(slice: &[T]) -> Result<[T; N], TryFromSliceError> {
|
||||
<&Self>::try_from(slice).map(|r| *r)
|
||||
}
|
||||
}
|
||||
|
||||
#[stable(feature = "try_from", since = "1.34.0")]
|
||||
impl<'a, T, const N: usize> TryFrom<&'a [T]> for &'a [T; N] {
|
||||
type Error = TryFromSliceError;
|
||||
|
||||
fn try_from(slice: &[T]) -> Result<&[T; N], TryFromSliceError> {
|
||||
if slice.len() == N {
|
||||
let ptr = slice.as_ptr() as *const [T; N];
|
||||
// SAFETY: ok because we just checked that the length fits
|
||||
unsafe { Ok(&*ptr) }
|
||||
} else {
|
||||
Err(TryFromSliceError(()))
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
#[stable(feature = "try_from", since = "1.34.0")]
|
||||
impl<'a, T, const N: usize> TryFrom<&'a mut [T]> for &'a mut [T; N] {
|
||||
type Error = TryFromSliceError;
|
||||
|
||||
fn try_from(slice: &mut [T]) -> Result<&mut [T; N], TryFromSliceError> {
|
||||
if slice.len() == N {
|
||||
let ptr = slice.as_mut_ptr() as *mut [T; N];
|
||||
// SAFETY: ok because we just checked that the length fits
|
||||
unsafe { Ok(&mut *ptr) }
|
||||
} else {
|
||||
Err(TryFromSliceError(()))
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
impl<T: Hash, const N: usize> Hash for [T; N] {
|
||||
fn hash<H: hash::Hasher>(&self, state: &mut H) {
|
||||
Hash::hash(&self[..], state)
|
||||
}
|
||||
}
|
||||
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
impl<T: fmt::Debug, const N: usize> fmt::Debug for [T; N] {
|
||||
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
|
||||
fmt::Debug::fmt(&&self[..], f)
|
||||
}
|
||||
}
|
||||
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
impl<'a, T, const N: usize> IntoIterator for &'a [T; N] {
|
||||
type Item = &'a T;
|
||||
type IntoIter = Iter<'a, T>;
|
||||
|
||||
fn into_iter(self) -> Iter<'a, T> {
|
||||
self.iter()
|
||||
}
|
||||
}
|
||||
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
impl<'a, T, const N: usize> IntoIterator for &'a mut [T; N] {
|
||||
type Item = &'a mut T;
|
||||
type IntoIter = IterMut<'a, T>;
|
||||
|
||||
fn into_iter(self) -> IterMut<'a, T> {
|
||||
self.iter_mut()
|
||||
}
|
||||
}
|
||||
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
impl<A, B, const N: usize> PartialEq<[B; N]> for [A; N]
|
||||
where
|
||||
A: PartialEq<B>,
|
||||
{
|
||||
#[inline]
|
||||
fn eq(&self, other: &[B; N]) -> bool {
|
||||
self[..] == other[..]
|
||||
}
|
||||
#[inline]
|
||||
fn ne(&self, other: &[B; N]) -> bool {
|
||||
self[..] != other[..]
|
||||
}
|
||||
}
|
||||
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
impl<A, B, const N: usize> PartialEq<[B]> for [A; N]
|
||||
where
|
||||
A: PartialEq<B>,
|
||||
{
|
||||
#[inline]
|
||||
fn eq(&self, other: &[B]) -> bool {
|
||||
self[..] == other[..]
|
||||
}
|
||||
#[inline]
|
||||
fn ne(&self, other: &[B]) -> bool {
|
||||
self[..] != other[..]
|
||||
}
|
||||
}
|
||||
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
impl<A, B, const N: usize> PartialEq<[A; N]> for [B]
|
||||
where
|
||||
B: PartialEq<A>,
|
||||
{
|
||||
#[inline]
|
||||
fn eq(&self, other: &[A; N]) -> bool {
|
||||
self[..] == other[..]
|
||||
}
|
||||
#[inline]
|
||||
fn ne(&self, other: &[A; N]) -> bool {
|
||||
self[..] != other[..]
|
||||
}
|
||||
}
|
||||
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
impl<'b, A, B, const N: usize> PartialEq<&'b [B]> for [A; N]
|
||||
where
|
||||
A: PartialEq<B>,
|
||||
{
|
||||
#[inline]
|
||||
fn eq(&self, other: &&'b [B]) -> bool {
|
||||
self[..] == other[..]
|
||||
}
|
||||
#[inline]
|
||||
fn ne(&self, other: &&'b [B]) -> bool {
|
||||
self[..] != other[..]
|
||||
}
|
||||
}
|
||||
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
impl<'b, A, B, const N: usize> PartialEq<[A; N]> for &'b [B]
|
||||
where
|
||||
B: PartialEq<A>,
|
||||
{
|
||||
#[inline]
|
||||
fn eq(&self, other: &[A; N]) -> bool {
|
||||
self[..] == other[..]
|
||||
}
|
||||
#[inline]
|
||||
fn ne(&self, other: &[A; N]) -> bool {
|
||||
self[..] != other[..]
|
||||
}
|
||||
}
|
||||
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
impl<'b, A, B, const N: usize> PartialEq<&'b mut [B]> for [A; N]
|
||||
where
|
||||
A: PartialEq<B>,
|
||||
{
|
||||
#[inline]
|
||||
fn eq(&self, other: &&'b mut [B]) -> bool {
|
||||
self[..] == other[..]
|
||||
}
|
||||
#[inline]
|
||||
fn ne(&self, other: &&'b mut [B]) -> bool {
|
||||
self[..] != other[..]
|
||||
}
|
||||
}
|
||||
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
impl<'b, A, B, const N: usize> PartialEq<[A; N]> for &'b mut [B]
|
||||
where
|
||||
B: PartialEq<A>,
|
||||
{
|
||||
#[inline]
|
||||
fn eq(&self, other: &[A; N]) -> bool {
|
||||
self[..] == other[..]
|
||||
}
|
||||
#[inline]
|
||||
fn ne(&self, other: &[A; N]) -> bool {
|
||||
self[..] != other[..]
|
||||
}
|
||||
}
|
||||
|
||||
// NOTE: some less important impls are omitted to reduce code bloat
|
||||
// __impl_slice_eq2! { [A; $N], &'b [B; $N] }
|
||||
// __impl_slice_eq2! { [A; $N], &'b mut [B; $N] }
|
||||
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
impl<T: Eq, const N: usize> Eq for [T; N] {}
|
||||
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
impl<T: PartialOrd, const N: usize> PartialOrd for [T; N] {
|
||||
#[inline]
|
||||
fn partial_cmp(&self, other: &[T; N]) -> Option<Ordering> {
|
||||
PartialOrd::partial_cmp(&&self[..], &&other[..])
|
||||
}
|
||||
#[inline]
|
||||
fn lt(&self, other: &[T; N]) -> bool {
|
||||
PartialOrd::lt(&&self[..], &&other[..])
|
||||
}
|
||||
#[inline]
|
||||
fn le(&self, other: &[T; N]) -> bool {
|
||||
PartialOrd::le(&&self[..], &&other[..])
|
||||
}
|
||||
#[inline]
|
||||
fn ge(&self, other: &[T; N]) -> bool {
|
||||
PartialOrd::ge(&&self[..], &&other[..])
|
||||
}
|
||||
#[inline]
|
||||
fn gt(&self, other: &[T; N]) -> bool {
|
||||
PartialOrd::gt(&&self[..], &&other[..])
|
||||
}
|
||||
}
|
||||
|
||||
/// Implements comparison of arrays lexicographically.
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
impl<T: Ord, const N: usize> Ord for [T; N] {
|
||||
#[inline]
|
||||
fn cmp(&self, other: &[T; N]) -> Ordering {
|
||||
Ord::cmp(&&self[..], &&other[..])
|
||||
}
|
||||
}
|
||||
|
||||
// The Default impls cannot be generated using the array_impls! macro because
|
||||
// they require array literals.
|
||||
|
||||
macro_rules! array_impl_default {
|
||||
{$n:expr, $t:ident $($ts:ident)*} => {
|
||||
#[stable(since = "1.4.0", feature = "array_default")]
|
||||
impl<T> Default for [T; $n] where T: Default {
|
||||
fn default() -> [T; $n] {
|
||||
[$t::default(), $($ts::default()),*]
|
||||
}
|
||||
}
|
||||
array_impl_default!{($n - 1), $($ts)*}
|
||||
};
|
||||
{$n:expr,} => {
|
||||
#[stable(since = "1.4.0", feature = "array_default")]
|
||||
impl<T> Default for [T; $n] {
|
||||
fn default() -> [T; $n] { [] }
|
||||
}
|
||||
};
|
||||
}
|
||||
|
||||
array_impl_default! {32, T T T T T T T T T T T T T T T T T T T T T T T T T T T T T T T T}
|
||||
Reference in New Issue
Block a user