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Replace SliceExt with inherent [T] methods in libcore

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This commit is contained in:
Simon Sapin
2018-04-07 19:38:35 +02:00
parent de8ed6a1d6
commit 90f29fbdb1
9 changed files with 1418 additions and 1393 deletions
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src/liballoc/lib.rs
+1
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@@ -90,6 +90,7 @@
#![feature(collections_range)]
#![feature(const_fn)]
#![feature(core_intrinsics)]
#![cfg_attr(stage0, feature(core_slice_ext))]
#![feature(custom_attribute)]
#![feature(dropck_eyepatch)]
#![feature(exact_size_is_empty)]
src/liballoc/slice.rs
+5 -1391
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@@ -101,7 +101,7 @@
use core::mem::size_of;
use core::mem;
use core::ptr;
use core::slice as core_slice;
#[cfg(stage0)] use core::slice::SliceExt;
use core::{u8, u16, u32};
use borrow::{Borrow, BorrowMut, ToOwned};
@@ -171,1059 +171,12 @@ pub fn to_vec<T>(s: &[T]) -> Vec<T>
}
}
#[lang = "slice"]
#[cfg_attr(stage0, lang = "slice")]
#[cfg_attr(not(stage0), lang = "slice_alloc")]
#[cfg(not(test))]
impl<T> [T] {
/// Returns the number of elements in the slice.
///
/// # Examples
///
/// ```
/// let a = [1, 2, 3];
/// assert_eq!(a.len(), 3);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn len(&self) -> usize {
core_slice::SliceExt::len(self)
}
/// Returns `true` if the slice has a length of 0.
///
/// # Examples
///
/// ```
/// let a = [1, 2, 3];
/// assert!(!a.is_empty());
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn is_empty(&self) -> bool {
core_slice::SliceExt::is_empty(self)
}
/// Returns the first element of the slice, or `None` if it is empty.
///
/// # Examples
///
/// ```
/// let v = [10, 40, 30];
/// assert_eq!(Some(&10), v.first());
///
/// let w: &[i32] = &[];
/// assert_eq!(None, w.first());
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn first(&self) -> Option<&T> {
core_slice::SliceExt::first(self)
}
/// Returns a mutable pointer to the first element of the slice, or `None` if it is empty.
///
/// # Examples
///
/// ```
/// let x = &mut [0, 1, 2];
///
/// if let Some(first) = x.first_mut() {
/// *first = 5;
/// }
/// assert_eq!(x, &[5, 1, 2]);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn first_mut(&mut self) -> Option<&mut T> {
core_slice::SliceExt::first_mut(self)
}
/// Returns the first and all the rest of the elements of the slice, or `None` if it is empty.
///
/// # Examples
///
/// ```
/// let x = &[0, 1, 2];
///
/// if let Some((first, elements)) = x.split_first() {
/// assert_eq!(first, &0);
/// assert_eq!(elements, &[1, 2]);
/// }
/// ```
#[stable(feature = "slice_splits", since = "1.5.0")]
#[inline]
pub fn split_first(&self) -> Option<(&T, &[T])> {
core_slice::SliceExt::split_first(self)
}
/// Returns the first and all the rest of the elements of the slice, or `None` if it is empty.
///
/// # Examples
///
/// ```
/// let x = &mut [0, 1, 2];
///
/// if let Some((first, elements)) = x.split_first_mut() {
/// *first = 3;
/// elements[0] = 4;
/// elements[1] = 5;
/// }
/// assert_eq!(x, &[3, 4, 5]);
/// ```
#[stable(feature = "slice_splits", since = "1.5.0")]
#[inline]
pub fn split_first_mut(&mut self) -> Option<(&mut T, &mut [T])> {
core_slice::SliceExt::split_first_mut(self)
}
/// Returns the last and all the rest of the elements of the slice, or `None` if it is empty.
///
/// # Examples
///
/// ```
/// let x = &[0, 1, 2];
///
/// if let Some((last, elements)) = x.split_last() {
/// assert_eq!(last, &2);
/// assert_eq!(elements, &[0, 1]);
/// }
/// ```
#[stable(feature = "slice_splits", since = "1.5.0")]
#[inline]
pub fn split_last(&self) -> Option<(&T, &[T])> {
core_slice::SliceExt::split_last(self)
}
/// Returns the last and all the rest of the elements of the slice, or `None` if it is empty.
///
/// # Examples
///
/// ```
/// let x = &mut [0, 1, 2];
///
/// if let Some((last, elements)) = x.split_last_mut() {
/// *last = 3;
/// elements[0] = 4;
/// elements[1] = 5;
/// }
/// assert_eq!(x, &[4, 5, 3]);
/// ```
#[stable(feature = "slice_splits", since = "1.5.0")]
#[inline]
pub fn split_last_mut(&mut self) -> Option<(&mut T, &mut [T])> {
core_slice::SliceExt::split_last_mut(self)
}
/// Returns the last element of the slice, or `None` if it is empty.
///
/// # Examples
///
/// ```
/// let v = [10, 40, 30];
/// assert_eq!(Some(&30), v.last());
///
/// let w: &[i32] = &[];
/// assert_eq!(None, w.last());
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn last(&self) -> Option<&T> {
core_slice::SliceExt::last(self)
}
/// Returns a mutable pointer to the last item in the slice.
///
/// # Examples
///
/// ```
/// let x = &mut [0, 1, 2];
///
/// if let Some(last) = x.last_mut() {
/// *last = 10;
/// }
/// assert_eq!(x, &[0, 1, 10]);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn last_mut(&mut self) -> Option<&mut T> {
core_slice::SliceExt::last_mut(self)
}
/// Returns a reference to an element or subslice depending on the type of
/// index.
///
/// - If given a position, returns a reference to the element at that
/// position or `None` if out of bounds.
/// - If given a range, returns the subslice corresponding to that range,
/// or `None` if out of bounds.
///
/// # Examples
///
/// ```
/// let v = [10, 40, 30];
/// assert_eq!(Some(&40), v.get(1));
/// assert_eq!(Some(&[10, 40][..]), v.get(0..2));
/// assert_eq!(None, v.get(3));
/// assert_eq!(None, v.get(0..4));
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn get<I>(&self, index: I) -> Option<&I::Output>
where I: SliceIndex<Self>
{
core_slice::SliceExt::get(self, index)
}
/// Returns a mutable reference to an element or subslice depending on the
/// type of index (see [`get`]) or `None` if the index is out of bounds.
///
/// [`get`]: #method.get
///
/// # Examples
///
/// ```
/// let x = &mut [0, 1, 2];
///
/// if let Some(elem) = x.get_mut(1) {
/// *elem = 42;
/// }
/// assert_eq!(x, &[0, 42, 2]);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn get_mut<I>(&mut self, index: I) -> Option<&mut I::Output>
where I: SliceIndex<Self>
{
core_slice::SliceExt::get_mut(self, index)
}
/// Returns a reference to an element or subslice, without doing bounds
/// checking.
///
/// This is generally not recommended, use with caution! For a safe
/// alternative see [`get`].
///
/// [`get`]: #method.get
///
/// # Examples
///
/// ```
/// let x = &[1, 2, 4];
///
/// unsafe {
/// assert_eq!(x.get_unchecked(1), &2);
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub unsafe fn get_unchecked<I>(&self, index: I) -> &I::Output
where I: SliceIndex<Self>
{
core_slice::SliceExt::get_unchecked(self, index)
}
/// Returns a mutable reference to an element or subslice, without doing
/// bounds checking.
///
/// This is generally not recommended, use with caution! For a safe
/// alternative see [`get_mut`].
///
/// [`get_mut`]: #method.get_mut
///
/// # Examples
///
/// ```
/// let x = &mut [1, 2, 4];
///
/// unsafe {
/// let elem = x.get_unchecked_mut(1);
/// *elem = 13;
/// }
/// assert_eq!(x, &[1, 13, 4]);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub unsafe fn get_unchecked_mut<I>(&mut self, index: I) -> &mut I::Output
where I: SliceIndex<Self>
{
core_slice::SliceExt::get_unchecked_mut(self, index)
}
/// Returns a raw pointer to the slice's buffer.
///
/// The caller must ensure that the slice outlives the pointer this
/// function returns, or else it will end up pointing to garbage.
///
/// Modifying the container referenced by this slice may cause its buffer
/// to be reallocated, which would also make any pointers to it invalid.
///
/// # Examples
///
/// ```
/// let x = &[1, 2, 4];
/// let x_ptr = x.as_ptr();
///
/// unsafe {
/// for i in 0..x.len() {
/// assert_eq!(x.get_unchecked(i), &*x_ptr.offset(i as isize));
/// }
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn as_ptr(&self) -> *const T {
core_slice::SliceExt::as_ptr(self)
}
/// Returns an unsafe mutable pointer to the slice's buffer.
///
/// The caller must ensure that the slice outlives the pointer this
/// function returns, or else it will end up pointing to garbage.
///
/// Modifying the container referenced by this slice may cause its buffer
/// to be reallocated, which would also make any pointers to it invalid.
///
/// # Examples
///
/// ```
/// let x = &mut [1, 2, 4];
/// let x_ptr = x.as_mut_ptr();
///
/// unsafe {
/// for i in 0..x.len() {
/// *x_ptr.offset(i as isize) += 2;
/// }
/// }
/// assert_eq!(x, &[3, 4, 6]);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn as_mut_ptr(&mut self) -> *mut T {
core_slice::SliceExt::as_mut_ptr(self)
}
/// Swaps two elements in the slice.
///
/// # Arguments
///
/// * a - The index of the first element
/// * b - The index of the second element
///
/// # Panics
///
/// Panics if `a` or `b` are out of bounds.
///
/// # Examples
///
/// ```
/// let mut v = ["a", "b", "c", "d"];
/// v.swap(1, 3);
/// assert!(v == ["a", "d", "c", "b"]);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn swap(&mut self, a: usize, b: usize) {
core_slice::SliceExt::swap(self, a, b)
}
/// Reverses the order of elements in the slice, in place.
///
/// # Examples
///
/// ```
/// let mut v = [1, 2, 3];
/// v.reverse();
/// assert!(v == [3, 2, 1]);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn reverse(&mut self) {
core_slice::SliceExt::reverse(self)
}
/// Returns an iterator over the slice.
///
/// # Examples
///
/// ```
/// let x = &[1, 2, 4];
/// let mut iterator = x.iter();
///
/// assert_eq!(iterator.next(), Some(&1));
/// assert_eq!(iterator.next(), Some(&2));
/// assert_eq!(iterator.next(), Some(&4));
/// assert_eq!(iterator.next(), None);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn iter(&self) -> Iter<T> {
core_slice::SliceExt::iter(self)
}
/// Returns an iterator that allows modifying each value.
///
/// # Examples
///
/// ```
/// let x = &mut [1, 2, 4];
/// for elem in x.iter_mut() {
/// *elem += 2;
/// }
/// assert_eq!(x, &[3, 4, 6]);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn iter_mut(&mut self) -> IterMut<T> {
core_slice::SliceExt::iter_mut(self)
}
/// Returns an iterator over all contiguous windows of length
/// `size`. The windows overlap. If the slice is shorter than
/// `size`, the iterator returns no values.
///
/// # Panics
///
/// Panics if `size` is 0.
///
/// # Examples
///
/// ```
/// let slice = ['r', 'u', 's', 't'];
/// let mut iter = slice.windows(2);
/// assert_eq!(iter.next().unwrap(), &['r', 'u']);
/// assert_eq!(iter.next().unwrap(), &['u', 's']);
/// assert_eq!(iter.next().unwrap(), &['s', 't']);
/// assert!(iter.next().is_none());
/// ```
///
/// If the slice is shorter than `size`:
///
/// ```
/// let slice = ['f', 'o', 'o'];
/// let mut iter = slice.windows(4);
/// assert!(iter.next().is_none());
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn windows(&self, size: usize) -> Windows<T> {
core_slice::SliceExt::windows(self, size)
}
/// Returns an iterator over `chunk_size` elements of the slice at a
/// time. The chunks are slices and do not overlap. If `chunk_size` does
/// not divide the length of the slice, then the last chunk will
/// not have length `chunk_size`.
///
/// See [`exact_chunks`] for a variant of this iterator that returns chunks
/// of always exactly `chunk_size` elements.
///
/// # Panics
///
/// Panics if `chunk_size` is 0.
///
/// # Examples
///
/// ```
/// let slice = ['l', 'o', 'r', 'e', 'm'];
/// let mut iter = slice.chunks(2);
/// assert_eq!(iter.next().unwrap(), &['l', 'o']);
/// assert_eq!(iter.next().unwrap(), &['r', 'e']);
/// assert_eq!(iter.next().unwrap(), &['m']);
/// assert!(iter.next().is_none());
/// ```
///
/// [`exact_chunks`]: #method.exact_chunks
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn chunks(&self, chunk_size: usize) -> Chunks<T> {
core_slice::SliceExt::chunks(self, chunk_size)
}
/// Returns an iterator over `chunk_size` elements of the slice at a
/// time. The chunks are slices and do not overlap. If `chunk_size` does
/// not divide the length of the slice, then the last up to `chunk_size-1`
/// elements will be omitted.
///
/// Due to each chunk having exactly `chunk_size` elements, the compiler
/// can often optimize the resulting code better than in the case of
/// [`chunks`].
///
/// # Panics
///
/// Panics if `chunk_size` is 0.
///
/// # Examples
///
/// ```
/// #![feature(exact_chunks)]
///
/// let slice = ['l', 'o', 'r', 'e', 'm'];
/// let mut iter = slice.exact_chunks(2);
/// assert_eq!(iter.next().unwrap(), &['l', 'o']);
/// assert_eq!(iter.next().unwrap(), &['r', 'e']);
/// assert!(iter.next().is_none());
/// ```
///
/// [`chunks`]: #method.chunks
#[unstable(feature = "exact_chunks", issue = "47115")]
#[inline]
pub fn exact_chunks(&self, chunk_size: usize) -> ExactChunks<T> {
core_slice::SliceExt::exact_chunks(self, chunk_size)
}
/// Returns an iterator over `chunk_size` elements of the slice at a time.
/// The chunks are mutable slices, and do not overlap. If `chunk_size` does
/// not divide the length of the slice, then the last chunk will not
/// have length `chunk_size`.
///
/// See [`exact_chunks_mut`] for a variant of this iterator that returns chunks
/// of always exactly `chunk_size` elements.
///
/// # Panics
///
/// Panics if `chunk_size` is 0.
///
/// # Examples
///
/// ```
/// let v = &mut [0, 0, 0, 0, 0];
/// let mut count = 1;
///
/// for chunk in v.chunks_mut(2) {
/// for elem in chunk.iter_mut() {
/// *elem += count;
/// }
/// count += 1;
/// }
/// assert_eq!(v, &[1, 1, 2, 2, 3]);
/// ```
///
/// [`exact_chunks_mut`]: #method.exact_chunks_mut
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn chunks_mut(&mut self, chunk_size: usize) -> ChunksMut<T> {
core_slice::SliceExt::chunks_mut(self, chunk_size)
}
/// Returns an iterator over `chunk_size` elements of the slice at a time.
/// The chunks are mutable slices, and do not overlap. If `chunk_size` does
/// not divide the length of the slice, then the last up to `chunk_size-1`
/// elements will be omitted.
///
///
/// Due to each chunk having exactly `chunk_size` elements, the compiler
/// can often optimize the resulting code better than in the case of
/// [`chunks_mut`].
///
/// # Panics
///
/// Panics if `chunk_size` is 0.
///
/// # Examples
///
/// ```
/// #![feature(exact_chunks)]
///
/// let v = &mut [0, 0, 0, 0, 0];
/// let mut count = 1;
///
/// for chunk in v.exact_chunks_mut(2) {
/// for elem in chunk.iter_mut() {
/// *elem += count;
/// }
/// count += 1;
/// }
/// assert_eq!(v, &[1, 1, 2, 2, 0]);
/// ```
///
/// [`chunks_mut`]: #method.chunks_mut
#[unstable(feature = "exact_chunks", issue = "47115")]
#[inline]
pub fn exact_chunks_mut(&mut self, chunk_size: usize) -> ExactChunksMut<T> {
core_slice::SliceExt::exact_chunks_mut(self, chunk_size)
}
/// Divides one slice into two at an index.
///
/// The first will contain all indices from `[0, mid)` (excluding
/// the index `mid` itself) and the second will contain all
/// indices from `[mid, len)` (excluding the index `len` itself).
///
/// # Panics
///
/// Panics if `mid > len`.
///
/// # Examples
///
/// ```
/// let v = [1, 2, 3, 4, 5, 6];
///
/// {
/// let (left, right) = v.split_at(0);
/// assert!(left == []);
/// assert!(right == [1, 2, 3, 4, 5, 6]);
/// }
///
/// {
/// let (left, right) = v.split_at(2);
/// assert!(left == [1, 2]);
/// assert!(right == [3, 4, 5, 6]);
/// }
///
/// {
/// let (left, right) = v.split_at(6);
/// assert!(left == [1, 2, 3, 4, 5, 6]);
/// assert!(right == []);
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn split_at(&self, mid: usize) -> (&[T], &[T]) {
core_slice::SliceExt::split_at(self, mid)
}
/// Divides one mutable slice into two at an index.
///
/// The first will contain all indices from `[0, mid)` (excluding
/// the index `mid` itself) and the second will contain all
/// indices from `[mid, len)` (excluding the index `len` itself).
///
/// # Panics
///
/// Panics if `mid > len`.
///
/// # Examples
///
/// ```
/// let mut v = [1, 0, 3, 0, 5, 6];
/// // scoped to restrict the lifetime of the borrows
/// {
/// let (left, right) = v.split_at_mut(2);
/// assert!(left == [1, 0]);
/// assert!(right == [3, 0, 5, 6]);
/// left[1] = 2;
/// right[1] = 4;
/// }
/// assert!(v == [1, 2, 3, 4, 5, 6]);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn split_at_mut(&mut self, mid: usize) -> (&mut [T], &mut [T]) {
core_slice::SliceExt::split_at_mut(self, mid)
}
/// Returns an iterator over subslices separated by elements that match
/// `pred`. The matched element is not contained in the subslices.
///
/// # Examples
///
/// ```
/// let slice = [10, 40, 33, 20];
/// let mut iter = slice.split(|num| num % 3 == 0);
///
/// assert_eq!(iter.next().unwrap(), &[10, 40]);
/// assert_eq!(iter.next().unwrap(), &[20]);
/// assert!(iter.next().is_none());
/// ```
///
/// If the first element is matched, an empty slice will be the first item
/// returned by the iterator. Similarly, if the last element in the slice
/// is matched, an empty slice will be the last item returned by the
/// iterator:
///
/// ```
/// let slice = [10, 40, 33];
/// let mut iter = slice.split(|num| num % 3 == 0);
///
/// assert_eq!(iter.next().unwrap(), &[10, 40]);
/// assert_eq!(iter.next().unwrap(), &[]);
/// assert!(iter.next().is_none());
/// ```
///
/// If two matched elements are directly adjacent, an empty slice will be
/// present between them:
///
/// ```
/// let slice = [10, 6, 33, 20];
/// let mut iter = slice.split(|num| num % 3 == 0);
///
/// assert_eq!(iter.next().unwrap(), &[10]);
/// assert_eq!(iter.next().unwrap(), &[]);
/// assert_eq!(iter.next().unwrap(), &[20]);
/// assert!(iter.next().is_none());
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn split<F>(&self, pred: F) -> Split<T, F>
where F: FnMut(&T) -> bool
{
core_slice::SliceExt::split(self, pred)
}
/// Returns an iterator over mutable subslices separated by elements that
/// match `pred`. The matched element is not contained in the subslices.
///
/// # Examples
///
/// ```
/// let mut v = [10, 40, 30, 20, 60, 50];
///
/// for group in v.split_mut(|num| *num % 3 == 0) {
/// group[0] = 1;
/// }
/// assert_eq!(v, [1, 40, 30, 1, 60, 1]);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn split_mut<F>(&mut self, pred: F) -> SplitMut<T, F>
where F: FnMut(&T) -> bool
{
core_slice::SliceExt::split_mut(self, pred)
}
/// Returns an iterator over subslices separated by elements that match
/// `pred`, starting at the end of the slice and working backwards.
/// The matched element is not contained in the subslices.
///
/// # Examples
///
/// ```
///
/// let slice = [11, 22, 33, 0, 44, 55];
/// let mut iter = slice.rsplit(|num| *num == 0);
///
/// assert_eq!(iter.next().unwrap(), &[44, 55]);
/// assert_eq!(iter.next().unwrap(), &[11, 22, 33]);
/// assert_eq!(iter.next(), None);
/// ```
///
/// As with `split()`, if the first or last element is matched, an empty
/// slice will be the first (or last) item returned by the iterator.
///
/// ```
/// let v = &[0, 1, 1, 2, 3, 5, 8];
/// let mut it = v.rsplit(|n| *n % 2 == 0);
/// assert_eq!(it.next().unwrap(), &[]);
/// assert_eq!(it.next().unwrap(), &[3, 5]);
/// assert_eq!(it.next().unwrap(), &[1, 1]);
/// assert_eq!(it.next().unwrap(), &[]);
/// assert_eq!(it.next(), None);
/// ```
#[stable(feature = "slice_rsplit", since = "1.27.0")]
#[inline]
pub fn rsplit<F>(&self, pred: F) -> RSplit<T, F>
where F: FnMut(&T) -> bool
{
core_slice::SliceExt::rsplit(self, pred)
}
/// Returns an iterator over mutable subslices separated by elements that
/// match `pred`, starting at the end of the slice and working
/// backwards. The matched element is not contained in the subslices.
///
/// # Examples
///
/// ```
/// let mut v = [100, 400, 300, 200, 600, 500];
///
/// let mut count = 0;
/// for group in v.rsplit_mut(|num| *num % 3 == 0) {
/// count += 1;
/// group[0] = count;
/// }
/// assert_eq!(v, [3, 400, 300, 2, 600, 1]);
/// ```
///
#[stable(feature = "slice_rsplit", since = "1.27.0")]
#[inline]
pub fn rsplit_mut<F>(&mut self, pred: F) -> RSplitMut<T, F>
where F: FnMut(&T) -> bool
{
core_slice::SliceExt::rsplit_mut(self, pred)
}
/// Returns an iterator over subslices separated by elements that match
/// `pred`, limited to returning at most `n` items. The matched element is
/// not contained in the subslices.
///
/// The last element returned, if any, will contain the remainder of the
/// slice.
///
/// # Examples
///
/// Print the slice split once by numbers divisible by 3 (i.e. `[10, 40]`,
/// `[20, 60, 50]`):
///
/// ```
/// let v = [10, 40, 30, 20, 60, 50];
///
/// for group in v.splitn(2, |num| *num % 3 == 0) {
/// println!("{:?}", group);
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn splitn<F>(&self, n: usize, pred: F) -> SplitN<T, F>
where F: FnMut(&T) -> bool
{
core_slice::SliceExt::splitn(self, n, pred)
}
/// Returns an iterator over subslices separated by elements that match
/// `pred`, limited to returning at most `n` items. The matched element is
/// not contained in the subslices.
///
/// The last element returned, if any, will contain the remainder of the
/// slice.
///
/// # Examples
///
/// ```
/// let mut v = [10, 40, 30, 20, 60, 50];
///
/// for group in v.splitn_mut(2, |num| *num % 3 == 0) {
/// group[0] = 1;
/// }
/// assert_eq!(v, [1, 40, 30, 1, 60, 50]);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn splitn_mut<F>(&mut self, n: usize, pred: F) -> SplitNMut<T, F>
where F: FnMut(&T) -> bool
{
core_slice::SliceExt::splitn_mut(self, n, pred)
}
/// Returns an iterator over subslices separated by elements that match
/// `pred` limited to returning at most `n` items. This starts at the end of
/// the slice and works backwards. The matched element is not contained in
/// the subslices.
///
/// The last element returned, if any, will contain the remainder of the
/// slice.
///
/// # Examples
///
/// Print the slice split once, starting from the end, by numbers divisible
/// by 3 (i.e. `[50]`, `[10, 40, 30, 20]`):
///
/// ```
/// let v = [10, 40, 30, 20, 60, 50];
///
/// for group in v.rsplitn(2, |num| *num % 3 == 0) {
/// println!("{:?}", group);
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn rsplitn<F>(&self, n: usize, pred: F) -> RSplitN<T, F>
where F: FnMut(&T) -> bool
{
core_slice::SliceExt::rsplitn(self, n, pred)
}
/// Returns an iterator over subslices separated by elements that match
/// `pred` limited to returning at most `n` items. This starts at the end of
/// the slice and works backwards. The matched element is not contained in
/// the subslices.
///
/// The last element returned, if any, will contain the remainder of the
/// slice.
///
/// # Examples
///
/// ```
/// let mut s = [10, 40, 30, 20, 60, 50];
///
/// for group in s.rsplitn_mut(2, |num| *num % 3 == 0) {
/// group[0] = 1;
/// }
/// assert_eq!(s, [1, 40, 30, 20, 60, 1]);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn rsplitn_mut<F>(&mut self, n: usize, pred: F) -> RSplitNMut<T, F>
where F: FnMut(&T) -> bool
{
core_slice::SliceExt::rsplitn_mut(self, n, pred)
}
/// Returns `true` if the slice contains an element with the given value.
///
/// # Examples
///
/// ```
/// let v = [10, 40, 30];
/// assert!(v.contains(&30));
/// assert!(!v.contains(&50));
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn contains(&self, x: &T) -> bool
where T: PartialEq
{
core_slice::SliceExt::contains(self, x)
}
/// Returns `true` if `needle` is a prefix of the slice.
///
/// # Examples
///
/// ```
/// let v = [10, 40, 30];
/// assert!(v.starts_with(&[10]));
/// assert!(v.starts_with(&[10, 40]));
/// assert!(!v.starts_with(&[50]));
/// assert!(!v.starts_with(&[10, 50]));
/// ```
///
/// Always returns `true` if `needle` is an empty slice:
///
/// ```
/// let v = &[10, 40, 30];
/// assert!(v.starts_with(&[]));
/// let v: &[u8] = &[];
/// assert!(v.starts_with(&[]));
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn starts_with(&self, needle: &[T]) -> bool
where T: PartialEq
{
core_slice::SliceExt::starts_with(self, needle)
}
/// Returns `true` if `needle` is a suffix of the slice.
///
/// # Examples
///
/// ```
/// let v = [10, 40, 30];
/// assert!(v.ends_with(&[30]));
/// assert!(v.ends_with(&[40, 30]));
/// assert!(!v.ends_with(&[50]));
/// assert!(!v.ends_with(&[50, 30]));
/// ```
///
/// Always returns `true` if `needle` is an empty slice:
///
/// ```
/// let v = &[10, 40, 30];
/// assert!(v.ends_with(&[]));
/// let v: &[u8] = &[];
/// assert!(v.ends_with(&[]));
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn ends_with(&self, needle: &[T]) -> bool
where T: PartialEq
{
core_slice::SliceExt::ends_with(self, needle)
}
/// Binary searches this sorted slice for a given element.
///
/// If the value is found then `Ok` is returned, containing the
/// index of the matching element; if the value is not found then
/// `Err` is returned, containing the index where a matching
/// element could be inserted while maintaining sorted order.
///
/// # Examples
///
/// Looks up a series of four elements. The first is found, with a
/// uniquely determined position; the second and third are not
/// found; the fourth could match any position in `[1, 4]`.
///
/// ```
/// let s = [0, 1, 1, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55];
///
/// assert_eq!(s.binary_search(&13), Ok(9));
/// assert_eq!(s.binary_search(&4), Err(7));
/// assert_eq!(s.binary_search(&100), Err(13));
/// let r = s.binary_search(&1);
/// assert!(match r { Ok(1...4) => true, _ => false, });
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn binary_search(&self, x: &T) -> Result<usize, usize>
where T: Ord
{
core_slice::SliceExt::binary_search(self, x)
}
/// Binary searches this sorted slice with a comparator function.
///
/// The comparator function should implement an order consistent
/// with the sort order of the underlying slice, returning an
/// order code that indicates whether its argument is `Less`,
/// `Equal` or `Greater` the desired target.
///
/// If a matching value is found then returns `Ok`, containing
/// the index for the matched element; if no match is found then
/// `Err` is returned, containing the index where a matching
/// element could be inserted while maintaining sorted order.
///
/// # Examples
///
/// Looks up a series of four elements. The first is found, with a
/// uniquely determined position; the second and third are not
/// found; the fourth could match any position in `[1, 4]`.
///
/// ```
/// let s = [0, 1, 1, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55];
///
/// let seek = 13;
/// assert_eq!(s.binary_search_by(|probe| probe.cmp(&seek)), Ok(9));
/// let seek = 4;
/// assert_eq!(s.binary_search_by(|probe| probe.cmp(&seek)), Err(7));
/// let seek = 100;
/// assert_eq!(s.binary_search_by(|probe| probe.cmp(&seek)), Err(13));
/// let seek = 1;
/// let r = s.binary_search_by(|probe| probe.cmp(&seek));
/// assert!(match r { Ok(1...4) => true, _ => false, });
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn binary_search_by<'a, F>(&'a self, f: F) -> Result<usize, usize>
where F: FnMut(&'a T) -> Ordering
{
core_slice::SliceExt::binary_search_by(self, f)
}
/// Binary searches this sorted slice with a key extraction function.
///
/// Assumes that the slice is sorted by the key, for instance with
/// [`sort_by_key`] using the same key extraction function.
///
/// If a matching value is found then returns `Ok`, containing the
/// index for the matched element; if no match is found then `Err`
/// is returned, containing the index where a matching element could
/// be inserted while maintaining sorted order.
///
/// [`sort_by_key`]: #method.sort_by_key
///
/// # Examples
///
/// Looks up a series of four elements in a slice of pairs sorted by
/// their second elements. The first is found, with a uniquely
/// determined position; the second and third are not found; the
/// fourth could match any position in `[1, 4]`.
///
/// ```
/// let s = [(0, 0), (2, 1), (4, 1), (5, 1), (3, 1),
/// (1, 2), (2, 3), (4, 5), (5, 8), (3, 13),
/// (1, 21), (2, 34), (4, 55)];
///
/// assert_eq!(s.binary_search_by_key(&13, |&(a,b)| b), Ok(9));
/// assert_eq!(s.binary_search_by_key(&4, |&(a,b)| b), Err(7));
/// assert_eq!(s.binary_search_by_key(&100, |&(a,b)| b), Err(13));
/// let r = s.binary_search_by_key(&1, |&(a,b)| b);
/// assert!(match r { Ok(1...4) => true, _ => false, });
/// ```
#[stable(feature = "slice_binary_search_by_key", since = "1.10.0")]
#[inline]
pub fn binary_search_by_key<'a, B, F>(&'a self, b: &B, f: F) -> Result<usize, usize>
where F: FnMut(&'a T) -> B,
B: Ord
{
core_slice::SliceExt::binary_search_by_key(self, b, f)
}
#[cfg(stage0)]
slice_core_methods!();
/// Sorts the slice.
///
@@ -1402,345 +355,6 @@ macro_rules! sort_by_key {
sort_by_key!(usize, self, f)
}
/// Sorts the slice, but may not preserve the order of equal elements.
///
/// This sort is unstable (i.e. may reorder equal elements), in-place (i.e. does not allocate),
/// and `O(n log n)` worst-case.
///
/// # Current implementation
///
/// The current algorithm is based on [pattern-defeating quicksort][pdqsort] by Orson Peters,
/// which combines the fast average case of randomized quicksort with the fast worst case of
/// heapsort, while achieving linear time on slices with certain patterns. It uses some
/// randomization to avoid degenerate cases, but with a fixed seed to always provide
/// deterministic behavior.
///
/// It is typically faster than stable sorting, except in a few special cases, e.g. when the
/// slice consists of several concatenated sorted sequences.
///
/// # Examples
///
/// ```
/// let mut v = [-5, 4, 1, -3, 2];
///
/// v.sort_unstable();
/// assert!(v == [-5, -3, 1, 2, 4]);
/// ```
///
/// [pdqsort]: https://github.com/orlp/pdqsort
#[stable(feature = "sort_unstable", since = "1.20.0")]
#[inline]
pub fn sort_unstable(&mut self)
where T: Ord
{
core_slice::SliceExt::sort_unstable(self);
}
/// Sorts the slice with a comparator function, but may not preserve the order of equal
/// elements.
///
/// This sort is unstable (i.e. may reorder equal elements), in-place (i.e. does not allocate),
/// and `O(n log n)` worst-case.
///
/// # Current implementation
///
/// The current algorithm is based on [pattern-defeating quicksort][pdqsort] by Orson Peters,
/// which combines the fast average case of randomized quicksort with the fast worst case of
/// heapsort, while achieving linear time on slices with certain patterns. It uses some
/// randomization to avoid degenerate cases, but with a fixed seed to always provide
/// deterministic behavior.
///
/// It is typically faster than stable sorting, except in a few special cases, e.g. when the
/// slice consists of several concatenated sorted sequences.
///
/// # Examples
///
/// ```
/// let mut v = [5, 4, 1, 3, 2];
/// v.sort_unstable_by(|a, b| a.cmp(b));
/// assert!(v == [1, 2, 3, 4, 5]);
///
/// // reverse sorting
/// v.sort_unstable_by(|a, b| b.cmp(a));
/// assert!(v == [5, 4, 3, 2, 1]);
/// ```
///
/// [pdqsort]: https://github.com/orlp/pdqsort
#[stable(feature = "sort_unstable", since = "1.20.0")]
#[inline]
pub fn sort_unstable_by<F>(&mut self, compare: F)
where F: FnMut(&T, &T) -> Ordering
{
core_slice::SliceExt::sort_unstable_by(self, compare);
}
/// Sorts the slice with a key extraction function, but may not preserve the order of equal
/// elements.
///
/// This sort is unstable (i.e. may reorder equal elements), in-place (i.e. does not allocate),
/// and `O(m n log(m n))` worst-case, where the key function is `O(m)`.
///
/// # Current implementation
///
/// The current algorithm is based on [pattern-defeating quicksort][pdqsort] by Orson Peters,
/// which combines the fast average case of randomized quicksort with the fast worst case of
/// heapsort, while achieving linear time on slices with certain patterns. It uses some
/// randomization to avoid degenerate cases, but with a fixed seed to always provide
/// deterministic behavior.
///
/// # Examples
///
/// ```
/// let mut v = [-5i32, 4, 1, -3, 2];
///
/// v.sort_unstable_by_key(|k| k.abs());
/// assert!(v == [1, 2, -3, 4, -5]);
/// ```
///
/// [pdqsort]: https://github.com/orlp/pdqsort
#[stable(feature = "sort_unstable", since = "1.20.0")]
#[inline]
pub fn sort_unstable_by_key<K, F>(&mut self, f: F)
where F: FnMut(&T) -> K, K: Ord
{
core_slice::SliceExt::sort_unstable_by_key(self, f);
}
/// Rotates the slice in-place such that the first `mid` elements of the
/// slice move to the end while the last `self.len() - mid` elements move to
/// the front. After calling `rotate_left`, the element previously at index
/// `mid` will become the first element in the slice.
///
/// # Panics
///
/// This function will panic if `mid` is greater than the length of the
/// slice. Note that `mid == self.len()` does _not_ panic and is a no-op
/// rotation.
///
/// # Complexity
///
/// Takes linear (in `self.len()`) time.
///
/// # Examples
///
/// ```
/// let mut a = ['a', 'b', 'c', 'd', 'e', 'f'];
/// a.rotate_left(2);
/// assert_eq!(a, ['c', 'd', 'e', 'f', 'a', 'b']);
/// ```
///
/// Rotating a subslice:
///
/// ```
/// let mut a = ['a', 'b', 'c', 'd', 'e', 'f'];
/// a[1..5].rotate_left(1);
/// assert_eq!(a, ['a', 'c', 'd', 'e', 'b', 'f']);
/// ```
#[stable(feature = "slice_rotate", since = "1.26.0")]
pub fn rotate_left(&mut self, mid: usize) {
core_slice::SliceExt::rotate_left(self, mid);
}
/// Rotates the slice in-place such that the first `self.len() - k`
/// elements of the slice move to the end while the last `k` elements move
/// to the front. After calling `rotate_right`, the element previously at
/// index `self.len() - k` will become the first element in the slice.
///
/// # Panics
///
/// This function will panic if `k` is greater than the length of the
/// slice. Note that `k == self.len()` does _not_ panic and is a no-op
/// rotation.
///
/// # Complexity
///
/// Takes linear (in `self.len()`) time.
///
/// # Examples
///
/// ```
/// let mut a = ['a', 'b', 'c', 'd', 'e', 'f'];
/// a.rotate_right(2);
/// assert_eq!(a, ['e', 'f', 'a', 'b', 'c', 'd']);
/// ```
///
/// Rotate a subslice:
///
/// ```
/// let mut a = ['a', 'b', 'c', 'd', 'e', 'f'];
/// a[1..5].rotate_right(1);
/// assert_eq!(a, ['a', 'e', 'b', 'c', 'd', 'f']);
/// ```
#[stable(feature = "slice_rotate", since = "1.26.0")]
pub fn rotate_right(&mut self, k: usize) {
core_slice::SliceExt::rotate_right(self, k);
}
/// Copies the elements from `src` into `self`.
///
/// The length of `src` must be the same as `self`.
///
/// If `src` implements `Copy`, it can be more performant to use
/// [`copy_from_slice`].
///
/// # Panics
///
/// This function will panic if the two slices have different lengths.
///
/// # Examples
///
/// Cloning two elements from a slice into another:
///
/// ```
/// let src = [1, 2, 3, 4];
/// let mut dst = [0, 0];
///
/// dst.clone_from_slice(&src[2..]);
///
/// assert_eq!(src, [1, 2, 3, 4]);
/// assert_eq!(dst, [3, 4]);
/// ```
///
/// Rust enforces that there can only be one mutable reference with no
/// immutable references to a particular piece of data in a particular
/// scope. Because of this, attempting to use `clone_from_slice` on a
/// single slice will result in a compile failure:
///
/// ```compile_fail
/// let mut slice = [1, 2, 3, 4, 5];
///
/// slice[..2].clone_from_slice(&slice[3..]); // compile fail!
/// ```
///
/// To work around this, we can use [`split_at_mut`] to create two distinct
/// sub-slices from a slice:
///
/// ```
/// let mut slice = [1, 2, 3, 4, 5];
///
/// {
/// let (left, right) = slice.split_at_mut(2);
/// left.clone_from_slice(&right[1..]);
/// }
///
/// assert_eq!(slice, [4, 5, 3, 4, 5]);
/// ```
///
/// [`copy_from_slice`]: #method.copy_from_slice
/// [`split_at_mut`]: #method.split_at_mut
#[stable(feature = "clone_from_slice", since = "1.7.0")]
pub fn clone_from_slice(&mut self, src: &[T]) where T: Clone {
core_slice::SliceExt::clone_from_slice(self, src)
}
/// Copies all elements from `src` into `self`, using a memcpy.
///
/// The length of `src` must be the same as `self`.
///
/// If `src` does not implement `Copy`, use [`clone_from_slice`].
///
/// # Panics
///
/// This function will panic if the two slices have different lengths.
///
/// # Examples
///
/// Copying two elements from a slice into another:
///
/// ```
/// let src = [1, 2, 3, 4];
/// let mut dst = [0, 0];
///
/// dst.copy_from_slice(&src[2..]);
///
/// assert_eq!(src, [1, 2, 3, 4]);
/// assert_eq!(dst, [3, 4]);
/// ```
///
/// Rust enforces that there can only be one mutable reference with no
/// immutable references to a particular piece of data in a particular
/// scope. Because of this, attempting to use `copy_from_slice` on a
/// single slice will result in a compile failure:
///
/// ```compile_fail
/// let mut slice = [1, 2, 3, 4, 5];
///
/// slice[..2].copy_from_slice(&slice[3..]); // compile fail!
/// ```
///
/// To work around this, we can use [`split_at_mut`] to create two distinct
/// sub-slices from a slice:
///
/// ```
/// let mut slice = [1, 2, 3, 4, 5];
///
/// {
/// let (left, right) = slice.split_at_mut(2);
/// left.copy_from_slice(&right[1..]);
/// }
///
/// assert_eq!(slice, [4, 5, 3, 4, 5]);
/// ```
///
/// [`clone_from_slice`]: #method.clone_from_slice
/// [`split_at_mut`]: #method.split_at_mut
#[stable(feature = "copy_from_slice", since = "1.9.0")]
pub fn copy_from_slice(&mut self, src: &[T]) where T: Copy {
core_slice::SliceExt::copy_from_slice(self, src)
}
/// Swaps all elements in `self` with those in `other`.
///
/// The length of `other` must be the same as `self`.
///
/// # Panics
///
/// This function will panic if the two slices have different lengths.
///
/// # Example
///
/// Swapping two elements across slices:
///
/// ```
/// let mut slice1 = [0, 0];
/// let mut slice2 = [1, 2, 3, 4];
///
/// slice1.swap_with_slice(&mut slice2[2..]);
///
/// assert_eq!(slice1, [3, 4]);
/// assert_eq!(slice2, [1, 2, 0, 0]);
/// ```
///
/// Rust enforces that there can only be one mutable reference to a
/// particular piece of data in a particular scope. Because of this,
/// attempting to use `swap_with_slice` on a single slice will result in
/// a compile failure:
///
/// ```compile_fail
/// let mut slice = [1, 2, 3, 4, 5];
/// slice[..2].swap_with_slice(&mut slice[3..]); // compile fail!
/// ```
///
/// To work around this, we can use [`split_at_mut`] to create two distinct
/// mutable sub-slices from a slice:
///
/// ```
/// let mut slice = [1, 2, 3, 4, 5];
///
/// {
/// let (left, right) = slice.split_at_mut(2);
/// left.swap_with_slice(&mut right[1..]);
/// }
///
/// assert_eq!(slice, [4, 5, 3, 1, 2]);
/// ```
///
/// [`split_at_mut`]: #method.split_at_mut
#[stable(feature = "swap_with_slice", since = "1.27.0")]
pub fn swap_with_slice(&mut self, other: &mut [T]) {
core_slice::SliceExt::swap_with_slice(self, other)
}
/// Copies `self` into a new `Vec`.
///
/// # Examples
src/libcore/lib.rs
+1 -1
View File
@@ -229,7 +229,7 @@ pub mod heap {
#[allow(unused_macros)]
macro_rules! vector_impl { ($([$f:ident, $($args:tt)*]),*) => { $($f!($($args)*);)* } }
#[path = "../stdsimd/coresimd/mod.rs"]
#[allow(missing_docs, missing_debug_implementations, dead_code)]
#[allow(missing_docs, missing_debug_implementations, dead_code, unused_imports)]
#[unstable(feature = "stdsimd", issue = "48556")]
#[cfg(not(stage0))] // allow changes to how stdsimd works in stage0
mod coresimd;
src/libcore/prelude/v1.rs
+1
View File
@@ -58,6 +58,7 @@
// Re-exported extension traits for primitive types
#[stable(feature = "core_prelude", since = "1.4.0")]
#[doc(no_inline)]
#[cfg(stage0)]
pub use slice::SliceExt;
#[stable(feature = "core_prelude", since = "1.4.0")]
#[doc(no_inline)]
src/libcore/slice/mod.rs
+1404
View File
@@ -755,6 +755,1410 @@ fn sort_unstable_by_key<B, F>(&mut self, mut f: F)
}
}
// FIXME: remove (inline) this macro and the SliceExt trait
// when updating to a bootstrap compiler that has the new lang items.
#[cfg_attr(stage0, macro_export)]
#[unstable(feature = "core_slice_ext", issue = "32110")]
macro_rules! slice_core_methods { () => {
/// Returns the number of elements in the slice.
///
/// # Examples
///
/// ```
/// let a = [1, 2, 3];
/// assert_eq!(a.len(), 3);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn len(&self) -> usize {
SliceExt::len(self)
}
/// Returns `true` if the slice has a length of 0.
///
/// # Examples
///
/// ```
/// let a = [1, 2, 3];
/// assert!(!a.is_empty());
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn is_empty(&self) -> bool {
SliceExt::is_empty(self)
}
/// Returns the first element of the slice, or `None` if it is empty.
///
/// # Examples
///
/// ```
/// let v = [10, 40, 30];
/// assert_eq!(Some(&10), v.first());
///
/// let w: &[i32] = &[];
/// assert_eq!(None, w.first());
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn first(&self) -> Option<&T> {
SliceExt::first(self)
}
/// Returns a mutable pointer to the first element of the slice, or `None` if it is empty.
///
/// # Examples
///
/// ```
/// let x = &mut [0, 1, 2];
///
/// if let Some(first) = x.first_mut() {
/// *first = 5;
/// }
/// assert_eq!(x, &[5, 1, 2]);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn first_mut(&mut self) -> Option<&mut T> {
SliceExt::first_mut(self)
}
/// Returns the first and all the rest of the elements of the slice, or `None` if it is empty.
///
/// # Examples
///
/// ```
/// let x = &[0, 1, 2];
///
/// if let Some((first, elements)) = x.split_first() {
/// assert_eq!(first, &0);
/// assert_eq!(elements, &[1, 2]);
/// }
/// ```
#[stable(feature = "slice_splits", since = "1.5.0")]
#[inline]
pub fn split_first(&self) -> Option<(&T, &[T])> {
SliceExt::split_first(self)
}
/// Returns the first and all the rest of the elements of the slice, or `None` if it is empty.
///
/// # Examples
///
/// ```
/// let x = &mut [0, 1, 2];
///
/// if let Some((first, elements)) = x.split_first_mut() {
/// *first = 3;
/// elements[0] = 4;
/// elements[1] = 5;
/// }
/// assert_eq!(x, &[3, 4, 5]);
/// ```
#[stable(feature = "slice_splits", since = "1.5.0")]
#[inline]
pub fn split_first_mut(&mut self) -> Option<(&mut T, &mut [T])> {
SliceExt::split_first_mut(self)
}
/// Returns the last and all the rest of the elements of the slice, or `None` if it is empty.
///
/// # Examples
///
/// ```
/// let x = &[0, 1, 2];
///
/// if let Some((last, elements)) = x.split_last() {
/// assert_eq!(last, &2);
/// assert_eq!(elements, &[0, 1]);
/// }
/// ```
#[stable(feature = "slice_splits", since = "1.5.0")]
#[inline]
pub fn split_last(&self) -> Option<(&T, &[T])> {
SliceExt::split_last(self)
}
/// Returns the last and all the rest of the elements of the slice, or `None` if it is empty.
///
/// # Examples
///
/// ```
/// let x = &mut [0, 1, 2];
///
/// if let Some((last, elements)) = x.split_last_mut() {
/// *last = 3;
/// elements[0] = 4;
/// elements[1] = 5;
/// }
/// assert_eq!(x, &[4, 5, 3]);
/// ```
#[stable(feature = "slice_splits", since = "1.5.0")]
#[inline]
pub fn split_last_mut(&mut self) -> Option<(&mut T, &mut [T])> {
SliceExt::split_last_mut(self)
}
/// Returns the last element of the slice, or `None` if it is empty.
///
/// # Examples
///
/// ```
/// let v = [10, 40, 30];
/// assert_eq!(Some(&30), v.last());
///
/// let w: &[i32] = &[];
/// assert_eq!(None, w.last());
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn last(&self) -> Option<&T> {
SliceExt::last(self)
}
/// Returns a mutable pointer to the last item in the slice.
///
/// # Examples
///
/// ```
/// let x = &mut [0, 1, 2];
///
/// if let Some(last) = x.last_mut() {
/// *last = 10;
/// }
/// assert_eq!(x, &[0, 1, 10]);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn last_mut(&mut self) -> Option<&mut T> {
SliceExt::last_mut(self)
}
/// Returns a reference to an element or subslice depending on the type of
/// index.
///
/// - If given a position, returns a reference to the element at that
/// position or `None` if out of bounds.
/// - If given a range, returns the subslice corresponding to that range,
/// or `None` if out of bounds.
///
/// # Examples
///
/// ```
/// let v = [10, 40, 30];
/// assert_eq!(Some(&40), v.get(1));
/// assert_eq!(Some(&[10, 40][..]), v.get(0..2));
/// assert_eq!(None, v.get(3));
/// assert_eq!(None, v.get(0..4));
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn get<I>(&self, index: I) -> Option<&I::Output>
where I: SliceIndex<Self>
{
SliceExt::get(self, index)
}
/// Returns a mutable reference to an element or subslice depending on the
/// type of index (see [`get`]) or `None` if the index is out of bounds.
///
/// [`get`]: #method.get
///
/// # Examples
///
/// ```
/// let x = &mut [0, 1, 2];
///
/// if let Some(elem) = x.get_mut(1) {
/// *elem = 42;
/// }
/// assert_eq!(x, &[0, 42, 2]);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn get_mut<I>(&mut self, index: I) -> Option<&mut I::Output>
where I: SliceIndex<Self>
{
SliceExt::get_mut(self, index)
}
/// Returns a reference to an element or subslice, without doing bounds
/// checking.
///
/// This is generally not recommended, use with caution! For a safe
/// alternative see [`get`].
///
/// [`get`]: #method.get
///
/// # Examples
///
/// ```
/// let x = &[1, 2, 4];
///
/// unsafe {
/// assert_eq!(x.get_unchecked(1), &2);
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub unsafe fn get_unchecked<I>(&self, index: I) -> &I::Output
where I: SliceIndex<Self>
{
SliceExt::get_unchecked(self, index)
}
/// Returns a mutable reference to an element or subslice, without doing
/// bounds checking.
///
/// This is generally not recommended, use with caution! For a safe
/// alternative see [`get_mut`].
///
/// [`get_mut`]: #method.get_mut
///
/// # Examples
///
/// ```
/// let x = &mut [1, 2, 4];
///
/// unsafe {
/// let elem = x.get_unchecked_mut(1);
/// *elem = 13;
/// }
/// assert_eq!(x, &[1, 13, 4]);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub unsafe fn get_unchecked_mut<I>(&mut self, index: I) -> &mut I::Output
where I: SliceIndex<Self>
{
SliceExt::get_unchecked_mut(self, index)
}
/// Returns a raw pointer to the slice's buffer.
///
/// The caller must ensure that the slice outlives the pointer this
/// function returns, or else it will end up pointing to garbage.
///
/// Modifying the container referenced by this slice may cause its buffer
/// to be reallocated, which would also make any pointers to it invalid.
///
/// # Examples
///
/// ```
/// let x = &[1, 2, 4];
/// let x_ptr = x.as_ptr();
///
/// unsafe {
/// for i in 0..x.len() {
/// assert_eq!(x.get_unchecked(i), &*x_ptr.offset(i as isize));
/// }
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn as_ptr(&self) -> *const T {
SliceExt::as_ptr(self)
}
/// Returns an unsafe mutable pointer to the slice's buffer.
///
/// The caller must ensure that the slice outlives the pointer this
/// function returns, or else it will end up pointing to garbage.
///
/// Modifying the container referenced by this slice may cause its buffer
/// to be reallocated, which would also make any pointers to it invalid.
///
/// # Examples
///
/// ```
/// let x = &mut [1, 2, 4];
/// let x_ptr = x.as_mut_ptr();
///
/// unsafe {
/// for i in 0..x.len() {
/// *x_ptr.offset(i as isize) += 2;
/// }
/// }
/// assert_eq!(x, &[3, 4, 6]);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn as_mut_ptr(&mut self) -> *mut T {
SliceExt::as_mut_ptr(self)
}
/// Swaps two elements in the slice.
///
/// # Arguments
///
/// * a - The index of the first element
/// * b - The index of the second element
///
/// # Panics
///
/// Panics if `a` or `b` are out of bounds.
///
/// # Examples
///
/// ```
/// let mut v = ["a", "b", "c", "d"];
/// v.swap(1, 3);
/// assert!(v == ["a", "d", "c", "b"]);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn swap(&mut self, a: usize, b: usize) {
SliceExt::swap(self, a, b)
}
/// Reverses the order of elements in the slice, in place.
///
/// # Examples
///
/// ```
/// let mut v = [1, 2, 3];
/// v.reverse();
/// assert!(v == [3, 2, 1]);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn reverse(&mut self) {
SliceExt::reverse(self)
}
/// Returns an iterator over the slice.
///
/// # Examples
///
/// ```
/// let x = &[1, 2, 4];
/// let mut iterator = x.iter();
///
/// assert_eq!(iterator.next(), Some(&1));
/// assert_eq!(iterator.next(), Some(&2));
/// assert_eq!(iterator.next(), Some(&4));
/// assert_eq!(iterator.next(), None);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn iter(&self) -> Iter<T> {
SliceExt::iter(self)
}
/// Returns an iterator that allows modifying each value.
///
/// # Examples
///
/// ```
/// let x = &mut [1, 2, 4];
/// for elem in x.iter_mut() {
/// *elem += 2;
/// }
/// assert_eq!(x, &[3, 4, 6]);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn iter_mut(&mut self) -> IterMut<T> {
SliceExt::iter_mut(self)
}
/// Returns an iterator over all contiguous windows of length
/// `size`. The windows overlap. If the slice is shorter than
/// `size`, the iterator returns no values.
///
/// # Panics
///
/// Panics if `size` is 0.
///
/// # Examples
///
/// ```
/// let slice = ['r', 'u', 's', 't'];
/// let mut iter = slice.windows(2);
/// assert_eq!(iter.next().unwrap(), &['r', 'u']);
/// assert_eq!(iter.next().unwrap(), &['u', 's']);
/// assert_eq!(iter.next().unwrap(), &['s', 't']);
/// assert!(iter.next().is_none());
/// ```
///
/// If the slice is shorter than `size`:
///
/// ```
/// let slice = ['f', 'o', 'o'];
/// let mut iter = slice.windows(4);
/// assert!(iter.next().is_none());
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn windows(&self, size: usize) -> Windows<T> {
SliceExt::windows(self, size)
}
/// Returns an iterator over `chunk_size` elements of the slice at a
/// time. The chunks are slices and do not overlap. If `chunk_size` does
/// not divide the length of the slice, then the last chunk will
/// not have length `chunk_size`.
///
/// See [`exact_chunks`] for a variant of this iterator that returns chunks
/// of always exactly `chunk_size` elements.
///
/// # Panics
///
/// Panics if `chunk_size` is 0.
///
/// # Examples
///
/// ```
/// let slice = ['l', 'o', 'r', 'e', 'm'];
/// let mut iter = slice.chunks(2);
/// assert_eq!(iter.next().unwrap(), &['l', 'o']);
/// assert_eq!(iter.next().unwrap(), &['r', 'e']);
/// assert_eq!(iter.next().unwrap(), &['m']);
/// assert!(iter.next().is_none());
/// ```
///
/// [`exact_chunks`]: #method.exact_chunks
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn chunks(&self, chunk_size: usize) -> Chunks<T> {
SliceExt::chunks(self, chunk_size)
}
/// Returns an iterator over `chunk_size` elements of the slice at a
/// time. The chunks are slices and do not overlap. If `chunk_size` does
/// not divide the length of the slice, then the last up to `chunk_size-1`
/// elements will be omitted.
///
/// Due to each chunk having exactly `chunk_size` elements, the compiler
/// can often optimize the resulting code better than in the case of
/// [`chunks`].
///
/// # Panics
///
/// Panics if `chunk_size` is 0.
///
/// # Examples
///
/// ```
/// #![feature(exact_chunks)]
///
/// let slice = ['l', 'o', 'r', 'e', 'm'];
/// let mut iter = slice.exact_chunks(2);
/// assert_eq!(iter.next().unwrap(), &['l', 'o']);
/// assert_eq!(iter.next().unwrap(), &['r', 'e']);
/// assert!(iter.next().is_none());
/// ```
///
/// [`chunks`]: #method.chunks
#[unstable(feature = "exact_chunks", issue = "47115")]
#[inline]
pub fn exact_chunks(&self, chunk_size: usize) -> ExactChunks<T> {
SliceExt::exact_chunks(self, chunk_size)
}
/// Returns an iterator over `chunk_size` elements of the slice at a time.
/// The chunks are mutable slices, and do not overlap. If `chunk_size` does
/// not divide the length of the slice, then the last chunk will not
/// have length `chunk_size`.
///
/// See [`exact_chunks_mut`] for a variant of this iterator that returns chunks
/// of always exactly `chunk_size` elements.
///
/// # Panics
///
/// Panics if `chunk_size` is 0.
///
/// # Examples
///
/// ```
/// let v = &mut [0, 0, 0, 0, 0];
/// let mut count = 1;
///
/// for chunk in v.chunks_mut(2) {
/// for elem in chunk.iter_mut() {
/// *elem += count;
/// }
/// count += 1;
/// }
/// assert_eq!(v, &[1, 1, 2, 2, 3]);
/// ```
///
/// [`exact_chunks_mut`]: #method.exact_chunks_mut
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn chunks_mut(&mut self, chunk_size: usize) -> ChunksMut<T> {
SliceExt::chunks_mut(self, chunk_size)
}
/// Returns an iterator over `chunk_size` elements of the slice at a time.
/// The chunks are mutable slices, and do not overlap. If `chunk_size` does
/// not divide the length of the slice, then the last up to `chunk_size-1`
/// elements will be omitted.
///
///
/// Due to each chunk having exactly `chunk_size` elements, the compiler
/// can often optimize the resulting code better than in the case of
/// [`chunks_mut`].
///
/// # Panics
///
/// Panics if `chunk_size` is 0.
///
/// # Examples
///
/// ```
/// #![feature(exact_chunks)]
///
/// let v = &mut [0, 0, 0, 0, 0];
/// let mut count = 1;
///
/// for chunk in v.exact_chunks_mut(2) {
/// for elem in chunk.iter_mut() {
/// *elem += count;
/// }
/// count += 1;
/// }
/// assert_eq!(v, &[1, 1, 2, 2, 0]);
/// ```
///
/// [`chunks_mut`]: #method.chunks_mut
#[unstable(feature = "exact_chunks", issue = "47115")]
#[inline]
pub fn exact_chunks_mut(&mut self, chunk_size: usize) -> ExactChunksMut<T> {
SliceExt::exact_chunks_mut(self, chunk_size)
}
/// Divides one slice into two at an index.
///
/// The first will contain all indices from `[0, mid)` (excluding
/// the index `mid` itself) and the second will contain all
/// indices from `[mid, len)` (excluding the index `len` itself).
///
/// # Panics
///
/// Panics if `mid > len`.
///
/// # Examples
///
/// ```
/// let v = [1, 2, 3, 4, 5, 6];
///
/// {
/// let (left, right) = v.split_at(0);
/// assert!(left == []);
/// assert!(right == [1, 2, 3, 4, 5, 6]);
/// }
///
/// {
/// let (left, right) = v.split_at(2);
/// assert!(left == [1, 2]);
/// assert!(right == [3, 4, 5, 6]);
/// }
///
/// {
/// let (left, right) = v.split_at(6);
/// assert!(left == [1, 2, 3, 4, 5, 6]);
/// assert!(right == []);
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn split_at(&self, mid: usize) -> (&[T], &[T]) {
SliceExt::split_at(self, mid)
}
/// Divides one mutable slice into two at an index.
///
/// The first will contain all indices from `[0, mid)` (excluding
/// the index `mid` itself) and the second will contain all
/// indices from `[mid, len)` (excluding the index `len` itself).
///
/// # Panics
///
/// Panics if `mid > len`.
///
/// # Examples
///
/// ```
/// let mut v = [1, 0, 3, 0, 5, 6];
/// // scoped to restrict the lifetime of the borrows
/// {
/// let (left, right) = v.split_at_mut(2);
/// assert!(left == [1, 0]);
/// assert!(right == [3, 0, 5, 6]);
/// left[1] = 2;
/// right[1] = 4;
/// }
/// assert!(v == [1, 2, 3, 4, 5, 6]);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn split_at_mut(&mut self, mid: usize) -> (&mut [T], &mut [T]) {
SliceExt::split_at_mut(self, mid)
}
/// Returns an iterator over subslices separated by elements that match
/// `pred`. The matched element is not contained in the subslices.
///
/// # Examples
///
/// ```
/// let slice = [10, 40, 33, 20];
/// let mut iter = slice.split(|num| num % 3 == 0);
///
/// assert_eq!(iter.next().unwrap(), &[10, 40]);
/// assert_eq!(iter.next().unwrap(), &[20]);
/// assert!(iter.next().is_none());
/// ```
///
/// If the first element is matched, an empty slice will be the first item
/// returned by the iterator. Similarly, if the last element in the slice
/// is matched, an empty slice will be the last item returned by the
/// iterator:
///
/// ```
/// let slice = [10, 40, 33];
/// let mut iter = slice.split(|num| num % 3 == 0);
///
/// assert_eq!(iter.next().unwrap(), &[10, 40]);
/// assert_eq!(iter.next().unwrap(), &[]);
/// assert!(iter.next().is_none());
/// ```
///
/// If two matched elements are directly adjacent, an empty slice will be
/// present between them:
///
/// ```
/// let slice = [10, 6, 33, 20];
/// let mut iter = slice.split(|num| num % 3 == 0);
///
/// assert_eq!(iter.next().unwrap(), &[10]);
/// assert_eq!(iter.next().unwrap(), &[]);
/// assert_eq!(iter.next().unwrap(), &[20]);
/// assert!(iter.next().is_none());
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn split<F>(&self, pred: F) -> Split<T, F>
where F: FnMut(&T) -> bool
{
SliceExt::split(self, pred)
}
/// Returns an iterator over mutable subslices separated by elements that
/// match `pred`. The matched element is not contained in the subslices.
///
/// # Examples
///
/// ```
/// let mut v = [10, 40, 30, 20, 60, 50];
///
/// for group in v.split_mut(|num| *num % 3 == 0) {
/// group[0] = 1;
/// }
/// assert_eq!(v, [1, 40, 30, 1, 60, 1]);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn split_mut<F>(&mut self, pred: F) -> SplitMut<T, F>
where F: FnMut(&T) -> bool
{
SliceExt::split_mut(self, pred)
}
/// Returns an iterator over subslices separated by elements that match
/// `pred`, starting at the end of the slice and working backwards.
/// The matched element is not contained in the subslices.
///
/// # Examples
///
/// ```
/// let slice = [11, 22, 33, 0, 44, 55];
/// let mut iter = slice.rsplit(|num| *num == 0);
///
/// assert_eq!(iter.next().unwrap(), &[44, 55]);
/// assert_eq!(iter.next().unwrap(), &[11, 22, 33]);
/// assert_eq!(iter.next(), None);
/// ```
///
/// As with `split()`, if the first or last element is matched, an empty
/// slice will be the first (or last) item returned by the iterator.
///
/// ```
/// let v = &[0, 1, 1, 2, 3, 5, 8];
/// let mut it = v.rsplit(|n| *n % 2 == 0);
/// assert_eq!(it.next().unwrap(), &[]);
/// assert_eq!(it.next().unwrap(), &[3, 5]);
/// assert_eq!(it.next().unwrap(), &[1, 1]);
/// assert_eq!(it.next().unwrap(), &[]);
/// assert_eq!(it.next(), None);
/// ```
#[stable(feature = "slice_rsplit", since = "1.27.0")]
#[inline]
pub fn rsplit<F>(&self, pred: F) -> RSplit<T, F>
where F: FnMut(&T) -> bool
{
SliceExt::rsplit(self, pred)
}
/// Returns an iterator over mutable subslices separated by elements that
/// match `pred`, starting at the end of the slice and working
/// backwards. The matched element is not contained in the subslices.
///
/// # Examples
///
/// ```
/// let mut v = [100, 400, 300, 200, 600, 500];
///
/// let mut count = 0;
/// for group in v.rsplit_mut(|num| *num % 3 == 0) {
/// count += 1;
/// group[0] = count;
/// }
/// assert_eq!(v, [3, 400, 300, 2, 600, 1]);
/// ```
///
#[stable(feature = "slice_rsplit", since = "1.27.0")]
#[inline]
pub fn rsplit_mut<F>(&mut self, pred: F) -> RSplitMut<T, F>
where F: FnMut(&T) -> bool
{
SliceExt::rsplit_mut(self, pred)
}
/// Returns an iterator over subslices separated by elements that match
/// `pred`, limited to returning at most `n` items. The matched element is
/// not contained in the subslices.
///
/// The last element returned, if any, will contain the remainder of the
/// slice.
///
/// # Examples
///
/// Print the slice split once by numbers divisible by 3 (i.e. `[10, 40]`,
/// `[20, 60, 50]`):
///
/// ```
/// let v = [10, 40, 30, 20, 60, 50];
///
/// for group in v.splitn(2, |num| *num % 3 == 0) {
/// println!("{:?}", group);
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn splitn<F>(&self, n: usize, pred: F) -> SplitN<T, F>
where F: FnMut(&T) -> bool
{
SliceExt::splitn(self, n, pred)
}
/// Returns an iterator over subslices separated by elements that match
/// `pred`, limited to returning at most `n` items. The matched element is
/// not contained in the subslices.
///
/// The last element returned, if any, will contain the remainder of the
/// slice.
///
/// # Examples
///
/// ```
/// let mut v = [10, 40, 30, 20, 60, 50];
///
/// for group in v.splitn_mut(2, |num| *num % 3 == 0) {
/// group[0] = 1;
/// }
/// assert_eq!(v, [1, 40, 30, 1, 60, 50]);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn splitn_mut<F>(&mut self, n: usize, pred: F) -> SplitNMut<T, F>
where F: FnMut(&T) -> bool
{
SliceExt::splitn_mut(self, n, pred)
}
/// Returns an iterator over subslices separated by elements that match
/// `pred` limited to returning at most `n` items. This starts at the end of
/// the slice and works backwards. The matched element is not contained in
/// the subslices.
///
/// The last element returned, if any, will contain the remainder of the
/// slice.
///
/// # Examples
///
/// Print the slice split once, starting from the end, by numbers divisible
/// by 3 (i.e. `[50]`, `[10, 40, 30, 20]`):
///
/// ```
/// let v = [10, 40, 30, 20, 60, 50];
///
/// for group in v.rsplitn(2, |num| *num % 3 == 0) {
/// println!("{:?}", group);
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn rsplitn<F>(&self, n: usize, pred: F) -> RSplitN<T, F>
where F: FnMut(&T) -> bool
{
SliceExt::rsplitn(self, n, pred)
}
/// Returns an iterator over subslices separated by elements that match
/// `pred` limited to returning at most `n` items. This starts at the end of
/// the slice and works backwards. The matched element is not contained in
/// the subslices.
///
/// The last element returned, if any, will contain the remainder of the
/// slice.
///
/// # Examples
///
/// ```
/// let mut s = [10, 40, 30, 20, 60, 50];
///
/// for group in s.rsplitn_mut(2, |num| *num % 3 == 0) {
/// group[0] = 1;
/// }
/// assert_eq!(s, [1, 40, 30, 20, 60, 1]);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn rsplitn_mut<F>(&mut self, n: usize, pred: F) -> RSplitNMut<T, F>
where F: FnMut(&T) -> bool
{
SliceExt::rsplitn_mut(self, n, pred)
}
/// Returns `true` if the slice contains an element with the given value.
///
/// # Examples
///
/// ```
/// let v = [10, 40, 30];
/// assert!(v.contains(&30));
/// assert!(!v.contains(&50));
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn contains(&self, x: &T) -> bool
where T: PartialEq
{
SliceExt::contains(self, x)
}
/// Returns `true` if `needle` is a prefix of the slice.
///
/// # Examples
///
/// ```
/// let v = [10, 40, 30];
/// assert!(v.starts_with(&[10]));
/// assert!(v.starts_with(&[10, 40]));
/// assert!(!v.starts_with(&[50]));
/// assert!(!v.starts_with(&[10, 50]));
/// ```
///
/// Always returns `true` if `needle` is an empty slice:
///
/// ```
/// let v = &[10, 40, 30];
/// assert!(v.starts_with(&[]));
/// let v: &[u8] = &[];
/// assert!(v.starts_with(&[]));
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn starts_with(&self, needle: &[T]) -> bool
where T: PartialEq
{
SliceExt::starts_with(self, needle)
}
/// Returns `true` if `needle` is a suffix of the slice.
///
/// # Examples
///
/// ```
/// let v = [10, 40, 30];
/// assert!(v.ends_with(&[30]));
/// assert!(v.ends_with(&[40, 30]));
/// assert!(!v.ends_with(&[50]));
/// assert!(!v.ends_with(&[50, 30]));
/// ```
///
/// Always returns `true` if `needle` is an empty slice:
///
/// ```
/// let v = &[10, 40, 30];
/// assert!(v.ends_with(&[]));
/// let v: &[u8] = &[];
/// assert!(v.ends_with(&[]));
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn ends_with(&self, needle: &[T]) -> bool
where T: PartialEq
{
SliceExt::ends_with(self, needle)
}
/// Binary searches this sorted slice for a given element.
///
/// If the value is found then `Ok` is returned, containing the
/// index of the matching element; if the value is not found then
/// `Err` is returned, containing the index where a matching
/// element could be inserted while maintaining sorted order.
///
/// # Examples
///
/// Looks up a series of four elements. The first is found, with a
/// uniquely determined position; the second and third are not
/// found; the fourth could match any position in `[1, 4]`.
///
/// ```
/// let s = [0, 1, 1, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55];
///
/// assert_eq!(s.binary_search(&13), Ok(9));
/// assert_eq!(s.binary_search(&4), Err(7));
/// assert_eq!(s.binary_search(&100), Err(13));
/// let r = s.binary_search(&1);
/// assert!(match r { Ok(1...4) => true, _ => false, });
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn binary_search(&self, x: &T) -> Result<usize, usize>
where T: Ord
{
SliceExt::binary_search(self, x)
}
/// Binary searches this sorted slice with a comparator function.
///
/// The comparator function should implement an order consistent
/// with the sort order of the underlying slice, returning an
/// order code that indicates whether its argument is `Less`,
/// `Equal` or `Greater` the desired target.
///
/// If a matching value is found then returns `Ok`, containing
/// the index for the matched element; if no match is found then
/// `Err` is returned, containing the index where a matching
/// element could be inserted while maintaining sorted order.
///
/// # Examples
///
/// Looks up a series of four elements. The first is found, with a
/// uniquely determined position; the second and third are not
/// found; the fourth could match any position in `[1, 4]`.
///
/// ```
/// let s = [0, 1, 1, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55];
///
/// let seek = 13;
/// assert_eq!(s.binary_search_by(|probe| probe.cmp(&seek)), Ok(9));
/// let seek = 4;
/// assert_eq!(s.binary_search_by(|probe| probe.cmp(&seek)), Err(7));
/// let seek = 100;
/// assert_eq!(s.binary_search_by(|probe| probe.cmp(&seek)), Err(13));
/// let seek = 1;
/// let r = s.binary_search_by(|probe| probe.cmp(&seek));
/// assert!(match r { Ok(1...4) => true, _ => false, });
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn binary_search_by<'a, F>(&'a self, f: F) -> Result<usize, usize>
where F: FnMut(&'a T) -> Ordering
{
SliceExt::binary_search_by(self, f)
}
/// Binary searches this sorted slice with a key extraction function.
///
/// Assumes that the slice is sorted by the key, for instance with
/// [`sort_by_key`] using the same key extraction function.
///
/// If a matching value is found then returns `Ok`, containing the
/// index for the matched element; if no match is found then `Err`
/// is returned, containing the index where a matching element could
/// be inserted while maintaining sorted order.
///
/// [`sort_by_key`]: #method.sort_by_key
///
/// # Examples
///
/// Looks up a series of four elements in a slice of pairs sorted by
/// their second elements. The first is found, with a uniquely
/// determined position; the second and third are not found; the
/// fourth could match any position in `[1, 4]`.
///
/// ```
/// let s = [(0, 0), (2, 1), (4, 1), (5, 1), (3, 1),
/// (1, 2), (2, 3), (4, 5), (5, 8), (3, 13),
/// (1, 21), (2, 34), (4, 55)];
///
/// assert_eq!(s.binary_search_by_key(&13, |&(a,b)| b), Ok(9));
/// assert_eq!(s.binary_search_by_key(&4, |&(a,b)| b), Err(7));
/// assert_eq!(s.binary_search_by_key(&100, |&(a,b)| b), Err(13));
/// let r = s.binary_search_by_key(&1, |&(a,b)| b);
/// assert!(match r { Ok(1...4) => true, _ => false, });
/// ```
#[stable(feature = "slice_binary_search_by_key", since = "1.10.0")]
#[inline]
pub fn binary_search_by_key<'a, B, F>(&'a self, b: &B, f: F) -> Result<usize, usize>
where F: FnMut(&'a T) -> B,
B: Ord
{
SliceExt::binary_search_by_key(self, b, f)
}
/// Sorts the slice, but may not preserve the order of equal elements.
///
/// This sort is unstable (i.e. may reorder equal elements), in-place (i.e. does not allocate),
/// and `O(n log n)` worst-case.
///
/// # Current implementation
///
/// The current algorithm is based on [pattern-defeating quicksort][pdqsort] by Orson Peters,
/// which combines the fast average case of randomized quicksort with the fast worst case of
/// heapsort, while achieving linear time on slices with certain patterns. It uses some
/// randomization to avoid degenerate cases, but with a fixed seed to always provide
/// deterministic behavior.
///
/// It is typically faster than stable sorting, except in a few special cases, e.g. when the
/// slice consists of several concatenated sorted sequences.
///
/// # Examples
///
/// ```
/// let mut v = [-5, 4, 1, -3, 2];
///
/// v.sort_unstable();
/// assert!(v == [-5, -3, 1, 2, 4]);
/// ```
///
/// [pdqsort]: https://github.com/orlp/pdqsort
#[stable(feature = "sort_unstable", since = "1.20.0")]
#[inline]
pub fn sort_unstable(&mut self)
where T: Ord
{
SliceExt::sort_unstable(self);
}
/// Sorts the slice with a comparator function, but may not preserve the order of equal
/// elements.
///
/// This sort is unstable (i.e. may reorder equal elements), in-place (i.e. does not allocate),
/// and `O(n log n)` worst-case.
///
/// # Current implementation
///
/// The current algorithm is based on [pattern-defeating quicksort][pdqsort] by Orson Peters,
/// which combines the fast average case of randomized quicksort with the fast worst case of
/// heapsort, while achieving linear time on slices with certain patterns. It uses some
/// randomization to avoid degenerate cases, but with a fixed seed to always provide
/// deterministic behavior.
///
/// It is typically faster than stable sorting, except in a few special cases, e.g. when the
/// slice consists of several concatenated sorted sequences.
///
/// # Examples
///
/// ```
/// let mut v = [5, 4, 1, 3, 2];
/// v.sort_unstable_by(|a, b| a.cmp(b));
/// assert!(v == [1, 2, 3, 4, 5]);
///
/// // reverse sorting
/// v.sort_unstable_by(|a, b| b.cmp(a));
/// assert!(v == [5, 4, 3, 2, 1]);
/// ```
///
/// [pdqsort]: https://github.com/orlp/pdqsort
#[stable(feature = "sort_unstable", since = "1.20.0")]
#[inline]
pub fn sort_unstable_by<F>(&mut self, compare: F)
where F: FnMut(&T, &T) -> Ordering
{
SliceExt::sort_unstable_by(self, compare);
}
/// Sorts the slice with a key extraction function, but may not preserve the order of equal
/// elements.
///
/// This sort is unstable (i.e. may reorder equal elements), in-place (i.e. does not allocate),
/// and `O(m n log(m n))` worst-case, where the key function is `O(m)`.
///
/// # Current implementation
///
/// The current algorithm is based on [pattern-defeating quicksort][pdqsort] by Orson Peters,
/// which combines the fast average case of randomized quicksort with the fast worst case of
/// heapsort, while achieving linear time on slices with certain patterns. It uses some
/// randomization to avoid degenerate cases, but with a fixed seed to always provide
/// deterministic behavior.
///
/// # Examples
///
/// ```
/// let mut v = [-5i32, 4, 1, -3, 2];
///
/// v.sort_unstable_by_key(|k| k.abs());
/// assert!(v == [1, 2, -3, 4, -5]);
/// ```
///
/// [pdqsort]: https://github.com/orlp/pdqsort
#[stable(feature = "sort_unstable", since = "1.20.0")]
#[inline]
pub fn sort_unstable_by_key<K, F>(&mut self, f: F)
where F: FnMut(&T) -> K, K: Ord
{
SliceExt::sort_unstable_by_key(self, f);
}
/// Rotates the slice in-place such that the first `mid` elements of the
/// slice move to the end while the last `self.len() - mid` elements move to
/// the front. After calling `rotate_left`, the element previously at index
/// `mid` will become the first element in the slice.
///
/// # Panics
///
/// This function will panic if `mid` is greater than the length of the
/// slice. Note that `mid == self.len()` does _not_ panic and is a no-op
/// rotation.
///
/// # Complexity
///
/// Takes linear (in `self.len()`) time.
///
/// # Examples
///
/// ```
/// let mut a = ['a', 'b', 'c', 'd', 'e', 'f'];
/// a.rotate_left(2);
/// assert_eq!(a, ['c', 'd', 'e', 'f', 'a', 'b']);
/// ```
///
/// Rotating a subslice:
///
/// ```
/// let mut a = ['a', 'b', 'c', 'd', 'e', 'f'];
/// a[1..5].rotate_left(1);
/// assert_eq!(a, ['a', 'c', 'd', 'e', 'b', 'f']);
/// ```
#[stable(feature = "slice_rotate", since = "1.26.0")]
pub fn rotate_left(&mut self, mid: usize) {
SliceExt::rotate_left(self, mid);
}
/// Rotates the slice in-place such that the first `self.len() - k`
/// elements of the slice move to the end while the last `k` elements move
/// to the front. After calling `rotate_right`, the element previously at
/// index `self.len() - k` will become the first element in the slice.
///
/// # Panics
///
/// This function will panic if `k` is greater than the length of the
/// slice. Note that `k == self.len()` does _not_ panic and is a no-op
/// rotation.
///
/// # Complexity
///
/// Takes linear (in `self.len()`) time.
///
/// # Examples
///
/// ```
/// let mut a = ['a', 'b', 'c', 'd', 'e', 'f'];
/// a.rotate_right(2);
/// assert_eq!(a, ['e', 'f', 'a', 'b', 'c', 'd']);
/// ```
///
/// Rotate a subslice:
///
/// ```
/// let mut a = ['a', 'b', 'c', 'd', 'e', 'f'];
/// a[1..5].rotate_right(1);
/// assert_eq!(a, ['a', 'e', 'b', 'c', 'd', 'f']);
/// ```
#[stable(feature = "slice_rotate", since = "1.26.0")]
pub fn rotate_right(&mut self, k: usize) {
SliceExt::rotate_right(self, k);
}
/// Copies the elements from `src` into `self`.
///
/// The length of `src` must be the same as `self`.
///
/// If `src` implements `Copy`, it can be more performant to use
/// [`copy_from_slice`].
///
/// # Panics
///
/// This function will panic if the two slices have different lengths.
///
/// # Examples
///
/// Cloning two elements from a slice into another:
///
/// ```
/// let src = [1, 2, 3, 4];
/// let mut dst = [0, 0];
///
/// dst.clone_from_slice(&src[2..]);
///
/// assert_eq!(src, [1, 2, 3, 4]);
/// assert_eq!(dst, [3, 4]);
/// ```
///
/// Rust enforces that there can only be one mutable reference with no
/// immutable references to a particular piece of data in a particular
/// scope. Because of this, attempting to use `clone_from_slice` on a
/// single slice will result in a compile failure:
///
/// ```compile_fail
/// let mut slice = [1, 2, 3, 4, 5];
///
/// slice[..2].clone_from_slice(&slice[3..]); // compile fail!
/// ```
///
/// To work around this, we can use [`split_at_mut`] to create two distinct
/// sub-slices from a slice:
///
/// ```
/// let mut slice = [1, 2, 3, 4, 5];
///
/// {
/// let (left, right) = slice.split_at_mut(2);
/// left.clone_from_slice(&right[1..]);
/// }
///
/// assert_eq!(slice, [4, 5, 3, 4, 5]);
/// ```
///
/// [`copy_from_slice`]: #method.copy_from_slice
/// [`split_at_mut`]: #method.split_at_mut
#[stable(feature = "clone_from_slice", since = "1.7.0")]
pub fn clone_from_slice(&mut self, src: &[T]) where T: Clone {
SliceExt::clone_from_slice(self, src)
}
/// Copies all elements from `src` into `self`, using a memcpy.
///
/// The length of `src` must be the same as `self`.
///
/// If `src` does not implement `Copy`, use [`clone_from_slice`].
///
/// # Panics
///
/// This function will panic if the two slices have different lengths.
///
/// # Examples
///
/// Copying two elements from a slice into another:
///
/// ```
/// let src = [1, 2, 3, 4];
/// let mut dst = [0, 0];
///
/// dst.copy_from_slice(&src[2..]);
///
/// assert_eq!(src, [1, 2, 3, 4]);
/// assert_eq!(dst, [3, 4]);
/// ```
///
/// Rust enforces that there can only be one mutable reference with no
/// immutable references to a particular piece of data in a particular
/// scope. Because of this, attempting to use `copy_from_slice` on a
/// single slice will result in a compile failure:
///
/// ```compile_fail
/// let mut slice = [1, 2, 3, 4, 5];
///
/// slice[..2].copy_from_slice(&slice[3..]); // compile fail!
/// ```
///
/// To work around this, we can use [`split_at_mut`] to create two distinct
/// sub-slices from a slice:
///
/// ```
/// let mut slice = [1, 2, 3, 4, 5];
///
/// {
/// let (left, right) = slice.split_at_mut(2);
/// left.copy_from_slice(&right[1..]);
/// }
///
/// assert_eq!(slice, [4, 5, 3, 4, 5]);
/// ```
///
/// [`clone_from_slice`]: #method.clone_from_slice
/// [`split_at_mut`]: #method.split_at_mut
#[stable(feature = "copy_from_slice", since = "1.9.0")]
pub fn copy_from_slice(&mut self, src: &[T]) where T: Copy {
SliceExt::copy_from_slice(self, src)
}
/// Swaps all elements in `self` with those in `other`.
///
/// The length of `other` must be the same as `self`.
///
/// # Panics
///
/// This function will panic if the two slices have different lengths.
///
/// # Example
///
/// Swapping two elements across slices:
///
/// ```
/// let mut slice1 = [0, 0];
/// let mut slice2 = [1, 2, 3, 4];
///
/// slice1.swap_with_slice(&mut slice2[2..]);
///
/// assert_eq!(slice1, [3, 4]);
/// assert_eq!(slice2, [1, 2, 0, 0]);
/// ```
///
/// Rust enforces that there can only be one mutable reference to a
/// particular piece of data in a particular scope. Because of this,
/// attempting to use `swap_with_slice` on a single slice will result in
/// a compile failure:
///
/// ```compile_fail
/// let mut slice = [1, 2, 3, 4, 5];
/// slice[..2].swap_with_slice(&mut slice[3..]); // compile fail!
/// ```
///
/// To work around this, we can use [`split_at_mut`] to create two distinct
/// mutable sub-slices from a slice:
///
/// ```
/// let mut slice = [1, 2, 3, 4, 5];
///
/// {
/// let (left, right) = slice.split_at_mut(2);
/// left.swap_with_slice(&mut right[1..]);
/// }
///
/// assert_eq!(slice, [4, 5, 3, 1, 2]);
/// ```
///
/// [`split_at_mut`]: #method.split_at_mut
#[stable(feature = "swap_with_slice", since = "1.27.0")]
pub fn swap_with_slice(&mut self, other: &mut [T]) {
SliceExt::swap_with_slice(self, other)
}
}}
#[lang = "slice"]
#[cfg(not(test))]
#[cfg(not(stage0))]
impl<T> [T] {
slice_core_methods!();
}
// FIXME: remove (inline) this macro
// when updating to a bootstrap compiler that has the new lang items.
#[cfg_attr(stage0, macro_export)]
#[unstable(feature = "core_slice_ext", issue = "32110")]
macro_rules! slice_u8_core_methods { () => {
src/librustc/middle/lang_items.rs
+1
View File
@@ -214,6 +214,7 @@ pub fn collect<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>) -> LanguageItems {
StrImplItem, "str", str_impl;
SliceImplItem, "slice", slice_impl;
SliceU8ImplItem, "slice_u8", slice_u8_impl;
SliceAllocImplItem, "slice_alloc", slice_alloc_impl;
SliceU8AllocImplItem, "slice_u8_alloc", slice_u8_alloc_impl;
ConstPtrImplItem, "const_ptr", const_ptr_impl;
MutPtrImplItem, "mut_ptr", mut_ptr_impl;
src/librustc_typeck/check/method/probe.rs
+3
View File
@@ -479,6 +479,9 @@ fn assemble_probe(&mut self, self_ty: Ty<'tcx>) {
let lang_def_id = lang_items.slice_u8_impl();
self.assemble_inherent_impl_for_primitive(lang_def_id);
let lang_def_id = lang_items.slice_alloc_impl();
self.assemble_inherent_impl_for_primitive(lang_def_id);
let lang_def_id = lang_items.slice_u8_alloc_impl();
self.assemble_inherent_impl_for_primitive(lang_def_id);
}
src/librustc_typeck/coherence/inherent_impls.rs
+1 -1
View File
@@ -138,7 +138,7 @@ fn visit_item(&mut self, item: &hir::Item) {
ty::TySlice(_) => {
self.check_primitive_impl(def_id,
lang_items.slice_impl(),
None,
lang_items.slice_alloc_impl(),
"slice",
"[T]",
item.span);
src/librustdoc/clean/inline.rs
+1
View File
@@ -290,6 +290,7 @@ pub fn build_impls(cx: &DocContext, did: DefId, auto_traits: bool) -> Vec<clean:
lang_items.str_impl(),
lang_items.slice_impl(),
lang_items.slice_u8_impl(),
lang_items.slice_alloc_impl(),
lang_items.slice_u8_alloc_impl(),
lang_items.const_ptr_impl(),
lang_items.mut_ptr_impl(),