#![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)]
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};
}
}
-#[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.
///
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
#[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;
// 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)]
}
}
+// 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 { () => {
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;
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);
}
ty::TySlice(_) => {
self.check_primitive_impl(def_id,
lang_items.slice_impl(),
- None,
+ lang_items.slice_alloc_impl(),
"slice",
"[T]",
item.span);
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(),
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