# Primitive Type slice
1.0.0[−]

A dynamically-sized view into a contiguous sequence, `[T]`. Contiguous here means that elements are laid out so that every element is the same distance from its neighbors.

See also the `std::slice` module.

Slices are a view into a block of memory represented as a pointer and a length.

    // slicing a Vec
    let vec = vec![1, 2, 3];
    let int_slice = &vec[..];
    // coercing an array to a slice
    let str_slice: &[&str] = &["one", "two", "three"];

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Slices are either mutable or shared. The shared slice type is `&[T]`, while the mutable slice type is `&mut [T]`, where `T` represents the element type. For example, you can mutate the block of memory that a mutable slice points to:

    let mut x = [1, 2, 3];
    let x = &mut x[..]; // Take a full slice of `x`.
    x[1] = 7;
    assert_eq!(x, &[1, 7, 3]);

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As slices store the length of the sequence they refer to, they have twice the size of pointers to `Sized` types. Also see the reference on dynamically sized types.

    let pointer_size = std::mem::size_of::<&u8>();
    assert_eq!(2 * pointer_size, std::mem::size_of::<&[u8]>());
    assert_eq!(2 * pointer_size, std::mem::size_of::<*const [u8]>());
    assert_eq!(2 * pointer_size, std::mem::size_of::<Box<[u8]>>());
    assert_eq!(2 * pointer_size, std::mem::size_of::<Rc<[u8]>>());

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## Implementations

### `impl<T> [T]`[src]

#### `pub const fn len(&self) -> usize` 1.0.0 (const: 1.39.0)[src]

Returns the number of elements in the slice.

# Examples

    let a = [1, 2, 3];
    assert_eq!(a.len(), 3);

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#### `pub const fn is_empty(&self) -> bool` 1.0.0 (const: 1.39.0)[src]

Returns `true` if the slice has a length of 0.

# Examples

    let a = [1, 2, 3];
    assert!(!a.is_empty());

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#### `pub const fn first(&self) -> Option<&T>`[src]

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());

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#### `pub const fn first_mut(&mut self) -> Option<&mut T>`[src]

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]);

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#### `pub const fn split_first(&self) -> Option<(&T, &[T])>`1.5.0[src]

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]);
    }

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#### `pub const fn split_first_mut(&mut self) -> Option<(&mut T, &mut [T])>`1.5.0[src]

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]);

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#### `pub const fn split_last(&self) -> Option<(&T, &[T])>`1.5.0[src]

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]);
    }

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#### `pub const fn split_last_mut(&mut self) -> Option<(&mut T, &mut [T])>`1.5.0[src]

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]);

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#### `pub const fn last(&self) -> Option<&T>`[src]

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());

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#### `pub const fn last_mut(&mut self) -> Option<&mut T>`[src]

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]);

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#### `pub fn get<I>(&self, index: I) -> Option<&<I as SliceIndex<[T]>>::Output> where
I: SliceIndex<[T]>,` [src]

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));

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#### `pub fn get_mut<I>(
&mut self,
index: I
) -> Option<&mut <I as SliceIndex<[T]>>::Output> where
I: SliceIndex<[T]>,` [src]

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.

# Examples

    let x = &mut [0, 1, 2];

    if let Some(elem) = x.get_mut(1) {
        *elem = 42;
    }
    assert_eq!(x, &[0, 42, 2]);

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#### `pub unsafe fn get_unchecked<I>(
&self,
index: I
) -> &<I as SliceIndex<[T]>>::Output where
I: SliceIndex<[T]>,` [src]

Returns a reference to an element or subslice, without doing bounds checking.

For a safe alternative see `get`.

# Safety

Calling this method with an out-of-bounds index is undefined behavior even if the resulting reference is not used.

# Examples

    let x = &[1, 2, 4];

    unsafe {
        assert_eq!(x.get_unchecked(1), &2);
    }

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#### `pub unsafe fn get_unchecked_mut<I>(
&mut self,
index: I
) -> &mut <I as SliceIndex<[T]>>::Output where
I: SliceIndex<[T]>,` [src]

Returns a mutable reference to an element or subslice, without doing bounds checking.

For a safe alternative see `get_mut`.

# Safety

Calling this method with an out-of-bounds index is undefined behavior even if the resulting reference is not used.

# Examples

    let x = &mut [1, 2, 4];

    unsafe {
        let elem = x.get_unchecked_mut(1);
        *elem = 13;
    }
    assert_eq!(x, &[1, 13, 4]);

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#### `pub const fn as_ptr(&self) -> *const T` 1.0.0 (const: 1.32.0)[src]

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.

The caller must also ensure that the memory the pointer (non-transitively) points to is never written to (except inside an `UnsafeCell`) using this pointer or any pointer derived from it. If you need to mutate the contents of the slice, use `as_mut_ptr`.

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.add(i));
        }
    }

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#### `pub const fn as_mut_ptr(&mut self) -> *mut T`[src]

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.add(i) += 2;
        }
    }
    assert_eq!(x, &[3, 4, 6]);

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#### `pub const fn as_ptr_range(&self) -> Range<*const T>ⓘ

### Notable traits for Range<A>

`impl<A> Iterator for Range<A> where
A: Step, type Item = A;`
`1.48.0[src]

Returns the two raw pointers spanning the slice.

The returned range is half-open, which means that the end pointer points one past the last element of the slice. This way, an empty slice is represented by two equal pointers, and the difference between the two pointers represents the size of the slice.

See `as_ptr` for warnings on using these pointers. The end pointer requires extra caution, as it does not point to a valid element in the slice.

This function is useful for interacting with foreign interfaces which use two pointers to refer to a range of elements in memory, as is common in C++.

It can also be useful to check if a pointer to an element refers to an element of this slice:

    let a = [1, 2, 3];
    let x = &a[1] as *const _;
    let y = &5 as *const _;

    assert!(a.as_ptr_range().contains(&x));
    assert!(!a.as_ptr_range().contains(&y));

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#### `pub const fn as_mut_ptr_range(&mut self) -> Range<*mut T>ⓘ

### Notable traits for Range<A>

`impl<A> Iterator for Range<A> where
A: Step, type Item = A;`
`1.48.0[src]

Returns the two unsafe mutable pointers spanning the slice.

The returned range is half-open, which means that the end pointer points one past the last element of the slice. This way, an empty slice is represented by two equal pointers, and the difference between the two pointers represents the size of the slice.

See `as_mut_ptr` for warnings on using these pointers. The end pointer requires extra caution, as it does not point to a valid element in the slice.

This function is useful for interacting with foreign interfaces which use two pointers to refer to a range of elements in memory, as is common in C++.

#### `pub fn swap(&mut self, a: usize, b: usize)`[src]

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"]);

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#### `pub fn reverse(&mut self)`[src]

Reverses the order of elements in the slice, in place.

# Examples

    let mut v = [1, 2, 3];
    v.reverse();
    assert!(v == [3, 2, 1]);

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#### `pub fn iter(&self) -> Iter<'_, T>ⓘ

### Notable traits for Iter<'a, T>

`impl<'a, T> Iterator for Iter<'a, T> type Item = &'a T;`
`[src]

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);

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#### `pub fn iter_mut(&mut self) -> IterMut<'_, T>ⓘ

### Notable traits for IterMut<'a, T>

`impl<'a, T> Iterator for IterMut<'a, T> type Item = &'a mut T;`
`[src]

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]);

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#### `pub fn windows(&self, size: usize) -> Windows<'_, T>ⓘ

### Notable traits for Windows<'a, T>

`impl<'a, T> Iterator for Windows<'a, T> type Item = &'a [T];`
`[src]

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());

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If the slice is shorter than `size`:

    let slice = ['f', 'o', 'o'];
    let mut iter = slice.windows(4);
    assert!(iter.next().is_none());

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#### `pub fn chunks(&self, chunk_size: usize) -> Chunks<'_, T>ⓘ

### Notable traits for Chunks<'a, T>

`impl<'a, T> Iterator for Chunks<'a, T> type Item = &'a [T];`
`[src]

Returns an iterator over `chunk_size` elements of the slice at a time, starting at the beginning of the slice.

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 `chunks_exact` for a variant of this iterator that returns chunks of always exactly `chunk_size` elements, and `rchunks` for the same iterator but starting at the end of the slice.

# 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());

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#### `pub fn chunks_mut(&mut self, chunk_size: usize) -> ChunksMut<'_, T>ⓘ

### Notable traits for ChunksMut<'a, T>

`impl<'a, T> Iterator for ChunksMut<'a, T> type Item = &'a mut [T];`
`[src]

Returns an iterator over `chunk_size` elements of the slice at a time, starting at the beginning of the slice.

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 `chunks_exact_mut` for a variant of this iterator that returns chunks of always exactly `chunk_size` elements, and `rchunks_mut` for the same iterator but starting at the end of the slice.

# 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]);

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#### `pub fn chunks_exact(&self, chunk_size: usize) -> ChunksExact<'_, T>ⓘ

### Notable traits for ChunksExact<'a, T>

`impl<'a, T> Iterator for ChunksExact<'a, T> type Item = &'a [T];`
`1.31.0[src]

Returns an iterator over `chunk_size` elements of the slice at a time, starting at the beginning of the slice.

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 and can be retrieved from the `remainder` function of the iterator.

Due to each chunk having exactly `chunk_size` elements, the compiler can often optimize the resulting code better than in the case of `chunks`.

See `chunks` for a variant of this iterator that also returns the remainder as a smaller chunk, and `rchunks_exact` for the same iterator but starting at the end of the slice.

# Panics

Panics if `chunk_size` is 0.

# Examples

    let slice = ['l', 'o', 'r', 'e', 'm'];
    let mut iter = slice.chunks_exact(2);
    assert_eq!(iter.next().unwrap(), &['l', 'o']);
    assert_eq!(iter.next().unwrap(), &['r', 'e']);
    assert!(iter.next().is_none());
    assert_eq!(iter.remainder(), &['m']);

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#### `pub fn chunks_exact_mut(&mut self, chunk_size: usize) -> ChunksExactMut<'_, T>ⓘ

### Notable traits for ChunksExactMut<'a, T>

`impl<'a, T> Iterator for ChunksExactMut<'a, T> type Item = &'a mut [T];`
`1.31.0[src]

Returns an iterator over `chunk_size` elements of the slice at a time, starting at the beginning of the slice.

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 and can be retrieved from the `into_remainder` function of the iterator.

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`.

See `chunks_mut` for a variant of this iterator that also returns the remainder as a smaller chunk, and `rchunks_exact_mut` for the same iterator but starting at the end of the slice.

# 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_exact_mut(2) {
        for elem in chunk.iter_mut() {
            *elem += count;
        }
        count += 1;
    }
    assert_eq!(v, &[1, 1, 2, 2, 0]);

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#### `pub unsafe fn as_chunks_unchecked<const N: usize>(&self) -> &[[T; N]]ⓘ

### Notable traits for &[u8]

`impl Read for &[u8]impl Write for &mut [u8]`
`[src]

🔬 This is a nightly-only experimental API. (`slice_as_chunks` #74985)

Splits the slice into a slice of `N`-element arrays, assuming that there’s no remainder.

# Safety

This may only be called when

- The slice splits exactly into `N`-element chunks (aka `self.len() % N == 0`).
- `N != 0`.

# Examples

    #![feature(slice_as_chunks)]
    let slice: &[char] = &['l', 'o', 'r', 'e', 'm', '!'];
    let chunks: &[[char; 1]] =
        // SAFETY: 1-element chunks never have remainder
        unsafe { slice.as_chunks_unchecked() };
    assert_eq!(chunks, &[['l'], ['o'], ['r'], ['e'], ['m'], ['!']]);
    let chunks: &[[char; 3]] =
        // SAFETY: The slice length (6) is a multiple of 3
        unsafe { slice.as_chunks_unchecked() };
    assert_eq!(chunks, &[['l', 'o', 'r'], ['e', 'm', '!']]);

    // These would be unsound:
    // let chunks: &[[_; 5]] = slice.as_chunks_unchecked() // The slice length is not a multiple of 5
    // let chunks: &[[_; 0]] = slice.as_chunks_unchecked() // Zero-length chunks are never allowed

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#### `pub fn as_chunks<const N: usize>(&self) -> (&[[T; N]], &[T])`[src]

🔬 This is a nightly-only experimental API. (`slice_as_chunks` #74985)

Splits the slice into a slice of `N`-element arrays, starting at the beginning of the slice, and a remainder slice with length strictly less than `N`.

# Panics

Panics if `N` is 0. This check will most probably get changed to a compile time error before this method gets stabilized.

# Examples

    #![feature(slice_as_chunks)]
    let slice = ['l', 'o', 'r', 'e', 'm'];
    let (chunks, remainder) = slice.as_chunks();
    assert_eq!(chunks, &[['l', 'o'], ['r', 'e']]);
    assert_eq!(remainder, &['m']);

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#### `pub fn as_rchunks<const N: usize>(&self) -> (&[T], &[[T; N]])`[src]

🔬 This is a nightly-only experimental API. (`slice_as_chunks` #74985)

Splits the slice into a slice of `N`-element arrays, starting at the end of the slice, and a remainder slice with length strictly less than `N`.

# Panics

Panics if `N` is 0. This check will most probably get changed to a compile time error before this method gets stabilized.

# Examples

    #![feature(slice_as_chunks)]
    let slice = ['l', 'o', 'r', 'e', 'm'];
    let (remainder, chunks) = slice.as_rchunks();
    assert_eq!(remainder, &['l']);
    assert_eq!(chunks, &[['o', 'r'], ['e', 'm']]);

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#### `pub fn array_chunks<const N: usize>(&self) -> ArrayChunks<'_, T, N>ⓘ

### Notable traits for ArrayChunks<'a, T, N>

`impl<'a, T, const N: usize> Iterator for ArrayChunks<'a, T, N> type Item = &'a [T; N];`
`[src]

🔬 This is a nightly-only experimental API. (`array_chunks` #74985)

Returns an iterator over `N` elements of the slice at a time, starting at the beginning of the slice.

The chunks are array references and do not overlap. If `N` does not divide the length of the slice, then the last up to `N-1` elements will be omitted and can be retrieved from the `remainder` function of the iterator.

This method is the const generic equivalent of `chunks_exact`.

# Panics

Panics if `N` is 0. This check will most probably get changed to a compile time error before this method gets stabilized.

# Examples

    #![feature(array_chunks)]
    let slice = ['l', 'o', 'r', 'e', 'm'];
    let mut iter = slice.array_chunks();
    assert_eq!(iter.next().unwrap(), &['l', 'o']);
    assert_eq!(iter.next().unwrap(), &['r', 'e']);
    assert!(iter.next().is_none());
    assert_eq!(iter.remainder(), &['m']);

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#### `pub unsafe fn as_chunks_unchecked_mut<const N: usize>(
&mut self
) -> &mut [[T; N]]ⓘ

### Notable traits for &[u8]

`impl Read for &[u8]impl Write for &mut [u8]`
`[src]

🔬 This is a nightly-only experimental API. (`slice_as_chunks` #74985)

Splits the slice into a slice of `N`-element arrays, assuming that there’s no remainder.

# Safety

This may only be called when

- The slice splits exactly into `N`-element chunks (aka `self.len() % N == 0`).
- `N != 0`.

# Examples

    #![feature(slice_as_chunks)]
    let slice: &mut [char] = &mut ['l', 'o', 'r', 'e', 'm', '!'];
    let chunks: &mut [[char; 1]] =
        // SAFETY: 1-element chunks never have remainder
        unsafe { slice.as_chunks_unchecked_mut() };
    chunks[0] = ['L'];
    assert_eq!(chunks, &[['L'], ['o'], ['r'], ['e'], ['m'], ['!']]);
    let chunks: &mut [[char; 3]] =
        // SAFETY: The slice length (6) is a multiple of 3
        unsafe { slice.as_chunks_unchecked_mut() };
    chunks[1] = ['a', 'x', '?'];
    assert_eq!(slice, &['L', 'o', 'r', 'a', 'x', '?']);

    // These would be unsound:
    // let chunks: &[[_; 5]] = slice.as_chunks_unchecked_mut() // The slice length is not a multiple of 5
    // let chunks: &[[_; 0]] = slice.as_chunks_unchecked_mut() // Zero-length chunks are never allowed

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#### `pub fn as_chunks_mut<const N: usize>(&mut self) -> (&mut [[T; N]], &mut [T])`[src]

🔬 This is a nightly-only experimental API. (`slice_as_chunks` #74985)

Splits the slice into a slice of `N`-element arrays, starting at the beginning of the slice, and a remainder slice with length strictly less than `N`.

# Panics

Panics if `N` is 0. This check will most probably get changed to a compile time error before this method gets stabilized.

# Examples

    #![feature(slice_as_chunks)]
    let v = &mut [0, 0, 0, 0, 0];
    let mut count = 1;

    let (chunks, remainder) = v.as_chunks_mut();
    remainder[0] = 9;
    for chunk in chunks {
        *chunk = [count; 2];
        count += 1;
    }
    assert_eq!(v, &[1, 1, 2, 2, 9]);

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#### `pub fn as_rchunks_mut<const N: usize>(&mut self) -> (&mut [T], &mut [[T; N]])`[src]

🔬 This is a nightly-only experimental API. (`slice_as_chunks` #74985)

Splits the slice into a slice of `N`-element arrays, starting at the end of the slice, and a remainder slice with length strictly less than `N`.

# Panics

Panics if `N` is 0. This check will most probably get changed to a compile time error before this method gets stabilized.

# Examples

    #![feature(slice_as_chunks)]
    let v = &mut [0, 0, 0, 0, 0];
    let mut count = 1;

    let (remainder, chunks) = v.as_rchunks_mut();
    remainder[0] = 9;
    for chunk in chunks {
        *chunk = [count; 2];
        count += 1;
    }
    assert_eq!(v, &[9, 1, 1, 2, 2]);

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#### `pub fn array_chunks_mut<const N: usize>(&mut self) -> ArrayChunksMut<'_, T, N>ⓘ

### Notable traits for ArrayChunksMut<'a, T, N>

`impl<'a, T, const N: usize> Iterator for ArrayChunksMut<'a, T, N> type Item = &'a mut [T; N];`
`[src]

🔬 This is a nightly-only experimental API. (`array_chunks` #74985)

Returns an iterator over `N` elements of the slice at a time, starting at the beginning of the slice.

The chunks are mutable array references and do not overlap. If `N` does not divide the length of the slice, then the last up to `N-1` elements will be omitted and can be retrieved from the `into_remainder` function of the iterator.

This method is the const generic equivalent of `chunks_exact_mut`.

# Panics

Panics if `N` is 0. This check will most probably get changed to a compile time error before this method gets stabilized.

# Examples

    #![feature(array_chunks)]
    let v = &mut [0, 0, 0, 0, 0];
    let mut count = 1;

    for chunk in v.array_chunks_mut() {
        *chunk = [count; 2];
        count += 1;
    }
    assert_eq!(v, &[1, 1, 2, 2, 0]);

Run

#### `pub fn array_windows<const N: usize>(&self) -> ArrayWindows<'_, T, N>ⓘ

### Notable traits for ArrayWindows<'a, T, N>

`impl<'a, T, const N: usize> Iterator for ArrayWindows<'a, T, N> type Item = &'a [T; N];`
`[src]

🔬 This is a nightly-only experimental API. (`array_windows` #75027)

Returns an iterator over overlapping windows of `N` elements of a slice, starting at the beginning of the slice.

This is the const generic equivalent of `windows`.

If `N` is greater than the size of the slice, it will return no windows.

# Panics

Panics if `N` is 0. This check will most probably get changed to a compile time error before this method gets stabilized.

# Examples

    #![feature(array_windows)]
    let slice = [0, 1, 2, 3];
    let mut iter = slice.array_windows();
    assert_eq!(iter.next().unwrap(), &[0, 1]);
    assert_eq!(iter.next().unwrap(), &[1, 2]);
    assert_eq!(iter.next().unwrap(), &[2, 3]);
    assert!(iter.next().is_none());

Run

#### `pub fn rchunks(&self, chunk_size: usize) -> RChunks<'_, T>ⓘ

### Notable traits for RChunks<'a, T>

`impl<'a, T> Iterator for RChunks<'a, T> type Item = &'a [T];`
`1.31.0[src]

Returns an iterator over `chunk_size` elements of the slice at a time, starting at the end of the slice.

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 `rchunks_exact` for a variant of this iterator that returns chunks of always exactly `chunk_size` elements, and `chunks` for the same iterator but starting at the beginning of the slice.

# Panics

Panics if `chunk_size` is 0.

# Examples

    let slice = ['l', 'o', 'r', 'e', 'm'];
    let mut iter = slice.rchunks(2);
    assert_eq!(iter.next().unwrap(), &['e', 'm']);
    assert_eq!(iter.next().unwrap(), &['o', 'r']);
    assert_eq!(iter.next().unwrap(), &['l']);
    assert!(iter.next().is_none());

Run

#### `pub fn rchunks_mut(&mut self, chunk_size: usize) -> RChunksMut<'_, T>ⓘ

### Notable traits for RChunksMut<'a, T>

`impl<'a, T> Iterator for RChunksMut<'a, T> type Item = &'a mut [T];`
`1.31.0[src]

Returns an iterator over `chunk_size` elements of the slice at a time, starting at the end of the slice.

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 `rchunks_exact_mut` for a variant of this iterator that returns chunks of always exactly `chunk_size` elements, and `chunks_mut` for the same iterator but starting at the beginning of the slice.

# Panics

Panics if `chunk_size` is 0.

# Examples

    let v = &mut [0, 0, 0, 0, 0];
    let mut count = 1;

    for chunk in v.rchunks_mut(2) {
        for elem in chunk.iter_mut() {
            *elem += count;
        }
        count += 1;
    }
    assert_eq!(v, &[3, 2, 2, 1, 1]);

Run

#### `pub fn rchunks_exact(&self, chunk_size: usize) -> RChunksExact<'_, T>ⓘ

### Notable traits for RChunksExact<'a, T>

`impl<'a, T> Iterator for RChunksExact<'a, T> type Item = &'a [T];`
`1.31.0[src]

Returns an iterator over `chunk_size` elements of the slice at a time, starting at the end of the slice.

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 and can be retrieved from the `remainder` function of the iterator.

Due to each chunk having exactly `chunk_size` elements, the compiler can often optimize the resulting code better than in the case of `chunks`.

See `rchunks` for a variant of this iterator that also returns the remainder as a smaller chunk, and `chunks_exact` for the same iterator but starting at the beginning of the slice.

# Panics

Panics if `chunk_size` is 0.

# Examples

    let slice = ['l', 'o', 'r', 'e', 'm'];
    let mut iter = slice.rchunks_exact(2);
    assert_eq!(iter.next().unwrap(), &['e', 'm']);
    assert_eq!(iter.next().unwrap(), &['o', 'r']);
    assert!(iter.next().is_none());
    assert_eq!(iter.remainder(), &['l']);

Run

#### `pub fn rchunks_exact_mut(&mut self, chunk_size: usize) -> RChunksExactMut<'_, T>ⓘ

### Notable traits for RChunksExactMut<'a, T>

`impl<'a, T> Iterator for RChunksExactMut<'a, T> type Item = &'a mut [T];`
`1.31.0[src]

Returns an iterator over `chunk_size` elements of the slice at a time, starting at the end of the slice.

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 and can be retrieved from the `into_remainder` function of the iterator.

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`.

See `rchunks_mut` for a variant of this iterator that also returns the remainder as a smaller chunk, and `chunks_exact_mut` for the same iterator but starting at the beginning of the slice.

# Panics

Panics if `chunk_size` is 0.

# Examples

    let v = &mut [0, 0, 0, 0, 0];
    let mut count = 1;

    for chunk in v.rchunks_exact_mut(2) {
        for elem in chunk.iter_mut() {
            *elem += count;
        }
        count += 1;
    }
    assert_eq!(v, &[0, 2, 2, 1, 1]);

Run

#### `pub fn group_by<F>(&self, pred: F) -> GroupBy<'_, T, F>ⓘ

### Notable traits for GroupBy<'a, T, P>

`impl<'a, T, P> Iterator for GroupBy<'a, T, P> where
T: 'a,
P: FnMut(&T, &T) -> bool, type Item = &'a [T];`
where
F: FnMut(&T, &T) -> bool,` [src]

🔬 This is a nightly-only experimental API. (`slice_group_by` #80552)

Returns an iterator over the slice producing non-overlapping runs of elements using the predicate to separate them.

The predicate is called on two elements following themselves, it means the predicate is called on `slice[0]` and `slice[1]` then on `slice[1]` and `slice[2]` and so on.

# Examples

    #![feature(slice_group_by)]

    let slice = &[1, 1, 1, 3, 3, 2, 2, 2];

    let mut iter = slice.group_by(|a, b| a == b);

    assert_eq!(iter.next(), Some(&[1, 1, 1][..]));
    assert_eq!(iter.next(), Some(&[3, 3][..]));
    assert_eq!(iter.next(), Some(&[2, 2, 2][..]));
    assert_eq!(iter.next(), None);

Run

This method can be used to extract the sorted subslices:

    #![feature(slice_group_by)]

    let slice = &[1, 1, 2, 3, 2, 3, 2, 3, 4];

    let mut iter = slice.group_by(|a, b| a <= b);

    assert_eq!(iter.next(), Some(&[1, 1, 2, 3][..]));
    assert_eq!(iter.next(), Some(&[2, 3][..]));
    assert_eq!(iter.next(), Some(&[2, 3, 4][..]));
    assert_eq!(iter.next(), None);

Run

#### `pub fn group_by_mut<F>(&mut self, pred: F) -> GroupByMut<'_, T, F>ⓘ

### Notable traits for GroupByMut<'a, T, P>

`impl<'a, T, P> Iterator for GroupByMut<'a, T, P> where
T: 'a,
P: FnMut(&T, &T) -> bool, type Item = &'a mut [T];`
where
F: FnMut(&T, &T) -> bool,` [src]

🔬 This is a nightly-only experimental API. (`slice_group_by` #80552)

Returns an iterator over the slice producing non-overlapping mutable runs of elements using the predicate to separate them.

The predicate is called on two elements following themselves, it means the predicate is called on `slice[0]` and `slice[1]` then on `slice[1]` and `slice[2]` and so on.

# Examples

    #![feature(slice_group_by)]

    let slice = &mut [1, 1, 1, 3, 3, 2, 2, 2];

    let mut iter = slice.group_by_mut(|a, b| a == b);

    assert_eq!(iter.next(), Some(&mut [1, 1, 1][..]));
    assert_eq!(iter.next(), Some(&mut [3, 3][..]));
    assert_eq!(iter.next(), Some(&mut [2, 2, 2][..]));
    assert_eq!(iter.next(), None);

Run

This method can be used to extract the sorted subslices:

    #![feature(slice_group_by)]

    let slice = &mut [1, 1, 2, 3, 2, 3, 2, 3, 4];

    let mut iter = slice.group_by_mut(|a, b| a <= b);

    assert_eq!(iter.next(), Some(&mut [1, 1, 2, 3][..]));
    assert_eq!(iter.next(), Some(&mut [2, 3][..]));
    assert_eq!(iter.next(), Some(&mut [2, 3, 4][..]));
    assert_eq!(iter.next(), None);

Run

#### `pub fn split_at(&self, mid: usize) -> (&[T], &[T])`[src]

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_eq!(left, []);
       assert_eq!(right, [1, 2, 3, 4, 5, 6]);
    }

    {
        let (left, right) = v.split_at(2);
        assert_eq!(left, [1, 2]);
        assert_eq!(right, [3, 4, 5, 6]);
    }

    {
        let (left, right) = v.split_at(6);
        assert_eq!(left, [1, 2, 3, 4, 5, 6]);
        assert_eq!(right, []);
    }

Run

#### `pub fn split_at_mut(&mut self, mid: usize) -> (&mut [T], &mut [T])`[src]

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];
    let (left, right) = v.split_at_mut(2);
    assert_eq!(left, [1, 0]);
    assert_eq!(right, [3, 0, 5, 6]);
    left[1] = 2;
    right[1] = 4;
    assert_eq!(v, [1, 2, 3, 4, 5, 6]);

Run

#### `pub fn split<F>(&self, pred: F) -> Split<'_, T, F>ⓘ

### Notable traits for Split<'a, T, P>

`impl<'a, T, P> Iterator for Split<'a, T, P> where
P: FnMut(&T) -> bool, type Item = &'a [T];`
where
F: FnMut(&T) -> bool,` [src]

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());

Run

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());

Run

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());

Run

#### `pub fn split_mut<F>(&mut self, pred: F) -> SplitMut<'_, T, F>ⓘ

### Notable traits for SplitMut<'a, T, P>

`impl<'a, T, P> Iterator for SplitMut<'a, T, P> where
P: FnMut(&T) -> bool, type Item = &'a mut [T];`
where
F: FnMut(&T) -> bool,` [src]

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]);

Run

#### `pub fn split_inclusive<F>(&self, pred: F) -> SplitInclusive<'_, T, F>ⓘ

### Notable traits for SplitInclusive<'a, T, P>

`impl<'a, T, P> Iterator for SplitInclusive<'a, T, P> where
P: FnMut(&T) -> bool, type Item = &'a [T];`
where
F: FnMut(&T) -> bool,` 1.51.0[src]

Returns an iterator over subslices separated by elements that match `pred`. The matched element is contained in the end of the previous subslice as a terminator.

# Examples

    let slice = [10, 40, 33, 20];
    let mut iter = slice.split_inclusive(|num| num % 3 == 0);

    assert_eq!(iter.next().unwrap(), &[10, 40, 33]);
    assert_eq!(iter.next().unwrap(), &[20]);
    assert!(iter.next().is_none());

Run

If the last element of the slice is matched, that element will be considered the terminator of the preceding slice. That slice will be the last item returned by the iterator.

    let slice = [3, 10, 40, 33];
    let mut iter = slice.split_inclusive(|num| num % 3 == 0);

    assert_eq!(iter.next().unwrap(), &[3]);
    assert_eq!(iter.next().unwrap(), &[10, 40, 33]);
    assert!(iter.next().is_none());

Run

#### `pub fn split_inclusive_mut<F>(&mut self, pred: F) -> SplitInclusiveMut<'_, T, F>ⓘ

### Notable traits for SplitInclusiveMut<'a, T, P>

`impl<'a, T, P> Iterator for SplitInclusiveMut<'a, T, P> where
P: FnMut(&T) -> bool, type Item = &'a mut [T];`
where
F: FnMut(&T) -> bool,` 1.51.0[src]

Returns an iterator over mutable subslices separated by elements that match `pred`. The matched element is contained in the previous subslice as a terminator.

# Examples

    let mut v = [10, 40, 30, 20, 60, 50];

    for group in v.split_inclusive_mut(|num| *num % 3 == 0) {
        let terminator_idx = group.len()-1;
        group[terminator_idx] = 1;
    }
    assert_eq!(v, [10, 40, 1, 20, 1, 1]);

Run

#### `pub fn rsplit<F>(&self, pred: F) -> RSplit<'_, T, F>ⓘ

### Notable traits for RSplit<'a, T, P>

`impl<'a, T, P> Iterator for RSplit<'a, T, P> where
P: FnMut(&T) -> bool, type Item = &'a [T];`
where
F: FnMut(&T) -> bool,` 1.27.0[src]

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);

Run

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);

Run

#### `pub fn rsplit_mut<F>(&mut self, pred: F) -> RSplitMut<'_, T, F>ⓘ

### Notable traits for RSplitMut<'a, T, P>

`impl<'a, T, P> Iterator for RSplitMut<'a, T, P> where
P: FnMut(&T) -> bool, type Item = &'a mut [T];`
where
F: FnMut(&T) -> bool,` 1.27.0[src]

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]);

Run

#### `pub fn splitn<F>(&self, n: usize, pred: F) -> SplitN<'_, T, F>ⓘ

### Notable traits for SplitN<'a, T, P>

`impl<'a, T, P> Iterator for SplitN<'a, T, P> where
P: FnMut(&T) -> bool, type Item = &'a [T];`
where
F: FnMut(&T) -> bool,` [src]

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);
    }

Run

#### `pub fn splitn_mut<F>(&mut self, n: usize, pred: F) -> SplitNMut<'_, T, F>ⓘ

### Notable traits for SplitNMut<'a, T, P>

`impl<'a, T, P> Iterator for SplitNMut<'a, T, P> where
P: FnMut(&T) -> bool, type Item = &'a mut [T];`
where
F: FnMut(&T) -> bool,` [src]

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]);

Run

#### `pub fn rsplitn<F>(&self, n: usize, pred: F) -> RSplitN<'_, T, F>ⓘ

### Notable traits for RSplitN<'a, T, P>

`impl<'a, T, P> Iterator for RSplitN<'a, T, P> where
P: FnMut(&T) -> bool, type Item = &'a [T];`
where
F: FnMut(&T) -> bool,` [src]

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);
    }

Run

#### `pub fn rsplitn_mut<F>(&mut self, n: usize, pred: F) -> RSplitNMut<'_, T, F>ⓘ

### Notable traits for RSplitNMut<'a, T, P>

`impl<'a, T, P> Iterator for RSplitNMut<'a, T, P> where
P: FnMut(&T) -> bool, type Item = &'a mut [T];`
where
F: FnMut(&T) -> bool,` [src]

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]);

Run

#### `pub fn contains(&self, x: &T) -> bool where
T: PartialEq<T>,` [src]

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));

Run

If you do not have an `&T`, but just an `&U` such that `T: Borrow<U>` (e.g. `String: Borrow<str>`), you can use `iter().any`:

    let v = [String::from("hello"), String::from("world")]; // slice of `String`
    assert!(v.iter().any(|e| e == "hello")); // search with `&str`
    assert!(!v.iter().any(|e| e == "hi"));

Run

#### `pub fn starts_with(&self, needle: &[T]) -> bool where
T: PartialEq<T>,` [src]

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]));

Run

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(&[]));

Run

#### `pub fn ends_with(&self, needle: &[T]) -> bool where
T: PartialEq<T>,` [src]

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]));

Run

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(&[]));

Run

#### `
#[must_use = "returns the subslice without modifying the original"]
pub fn strip_prefix<P>(&self, prefix: &P) -> Option<&[T]> where
T: PartialEq<T>,
P: SlicePattern<Item = T> + ?Sized,` 1.51.0[src]

Returns a subslice with the prefix removed.

If the slice starts with `prefix`, returns the subslice after the prefix, wrapped in `Some`. If `prefix` is empty, simply returns the original slice.

If the slice does not start with `prefix`, returns `None`.

# Examples

    let v = &[10, 40, 30];
    assert_eq!(v.strip_prefix(&[10]), Some(&[40, 30][..]));
    assert_eq!(v.strip_prefix(&[10, 40]), Some(&[30][..]));
    assert_eq!(v.strip_prefix(&[50]), None);
    assert_eq!(v.strip_prefix(&[10, 50]), None);

    let prefix : &str = "he";
    assert_eq!(b"hello".strip_prefix(prefix.as_bytes()),
               Some(b"llo".as_ref()));

Run

#### `
#[must_use = "returns the subslice without modifying the original"]
pub fn strip_suffix<P>(&self, suffix: &P) -> Option<&[T]> where
T: PartialEq<T>,
P: SlicePattern<Item = T> + ?Sized,` 1.51.0[src]

Returns a subslice with the suffix removed.

If the slice ends with `suffix`, returns the subslice before the suffix, wrapped in `Some`. If `suffix` is empty, simply returns the original slice.

If the slice does not end with `suffix`, returns `None`.

# Examples

    let v = &[10, 40, 30];
    assert_eq!(v.strip_suffix(&[30]), Some(&[10, 40][..]));
    assert_eq!(v.strip_suffix(&[40, 30]), Some(&[10][..]));
    assert_eq!(v.strip_suffix(&[50]), None);
    assert_eq!(v.strip_suffix(&[50, 30]), None);

Run

#### `pub fn binary_search(&self, x: &T) -> Result<usize, usize> where
T: Ord,` [src]

Binary searches this sorted slice for a given element.

If the value is found then `Result::Ok` is returned, containing the index of the matching element. If there are multiple matches, then any one of the matches could be returned. If the value is not found then `Result::Err` is returned, containing the index where a matching element could be inserted while maintaining sorted order.

See also `binary_search_by`, `binary_search_by_key`, and `partition_point`.

# 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, });

Run

If you want to insert an item to a sorted vector, while maintaining sort order:

    let mut s = vec![0, 1, 1, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55];
    let num = 42;
    let idx = s.binary_search(&num).unwrap_or_else(|x| x);
    s.insert(idx, num);
    assert_eq!(s, [0, 1, 1, 1, 1, 2, 3, 5, 8, 13, 21, 34, 42, 55]);

Run

#### `pub fn binary_search_by<'a, F>(&'a self, f: F) -> Result<usize, usize> where
F: FnMut(&'a T) -> Ordering,` [src]

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 the value is found then `Result::Ok` is returned, containing the index of the matching element. If there are multiple matches, then any one of the matches could be returned. If the value is not found then `Result::Err` is returned, containing the index where a matching element could be inserted while maintaining sorted order.

See also `binary_search`, `binary_search_by_key`, and `partition_point`.

# 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, });

Run

#### `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,` 1.10.0[src]

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 the value is found then `Result::Ok` is returned, containing the index of the matching element. If there are multiple matches, then any one of the matches could be returned. If the value is not found then `Result::Err` is returned, containing the index where a matching element could be inserted while maintaining sorted order.

See also `binary_search`, `binary_search_by`, and `partition_point`.

# 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, });

Run

#### `pub fn sort_unstable(&mut self) where
T: Ord,` 1.20.0[src]

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 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]);

Run

#### `pub fn sort_unstable_by<F>(&mut self, compare: F) where
F: FnMut(&T, &T) -> Ordering,` 1.20.0[src]

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.

The comparator function must define a total ordering for the elements in the slice. If the ordering is not total, the order of the elements is unspecified. An order is a total order if it is (for all `a`, `b` and `c`):

- total and antisymmetric: exactly one of `a < b`, `a == b` or `a > b` is true, and
- transitive, `a < b` and `b < c` implies `a < c`. The same must hold for both `==` and `>`.

For example, while `f64` doesn’t implement `Ord` because `NaN != NaN`, we can use `partial_cmp` as our sort function when we know the slice doesn’t contain a `NaN`.

    let mut floats = [5f64, 4.0, 1.0, 3.0, 2.0];
    floats.sort_unstable_by(|a, b| a.partial_cmp(b).unwrap());
    assert_eq!(floats, [1.0, 2.0, 3.0, 4.0, 5.0]);

Run

# Current implementation

The current algorithm is based on pattern-defeating quicksort 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]);

Run

#### `pub fn sort_unstable_by_key<K, F>(&mut self, f: F) where
F: FnMut(&T) -> K,
K: Ord,` 1.20.0[src]

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(n)) worst-case, where the key function is O(m).

# Current implementation

The current algorithm is based on pattern-defeating quicksort 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.

Due to its key calling strategy, `sort_unstable_by_key` is likely to be slower than `sort_by_cached_key` in cases where the key function is expensive.

# Examples

    let mut v = [-5i32, 4, 1, -3, 2];

    v.sort_unstable_by_key(|k| k.abs());
    assert!(v == [1, 2, -3, 4, -5]);

Run

#### `pub fn partition_at_index(
&mut self,
index: usize
) -> (&mut [T], &mut T, &mut [T]) where
T: Ord,` [src]

👎 Deprecated since 1.49.0:

use the select_nth_unstable() instead

🔬 This is a nightly-only experimental API. (`slice_partition_at_index` #55300)

Reorder the slice such that the element at `index` is at its final sorted position.

#### `pub fn partition_at_index_by<F>(
&mut self,
index: usize,
compare: F
) -> (&mut [T], &mut T, &mut [T]) where
F: FnMut(&T, &T) -> Ordering,` [src]

👎 Deprecated since 1.49.0:

use select_nth_unstable_by() instead

🔬 This is a nightly-only experimental API. (`slice_partition_at_index` #55300)

Reorder the slice with a comparator function such that the element at `index` is at its final sorted position.

#### `pub fn partition_at_index_by_key<K, F>(
&mut self,
index: usize,
f: F
) -> (&mut [T], &mut T, &mut [T]) where
F: FnMut(&T) -> K,
K: Ord,` [src]

👎 Deprecated since 1.49.0:

use the select_nth_unstable_by_key() instead

🔬 This is a nightly-only experimental API. (`slice_partition_at_index` #55300)

Reorder the slice with a key extraction function such that the element at `index` is at its final sorted position.

#### `pub fn select_nth_unstable(
&mut self,
index: usize
) -> (&mut [T], &mut T, &mut [T]) where
T: Ord,` 1.49.0[src]

Reorder the slice such that the element at `index` is at its final sorted position.

This reordering has the additional property that any value at position `i < index` will be less than or equal to any value at a position `j > index`. Additionally, this reordering is unstable (i.e. any number of equal elements may end up at position `index`), in-place (i.e. does not allocate), and O(n) worst-case. This function is also/ known as “kth element” in other libraries. It returns a triplet of the following values: all elements less than the one at the given index, the value at the given index, and all elements greater than the one at the given index.

# Current implementation

The current algorithm is based on the quickselect portion of the same quicksort algorithm used for `sort_unstable`.

# Panics

Panics when `index >= len()`, meaning it always panics on empty slices.

# Examples

    let mut v = [-5i32, 4, 1, -3, 2];

    // Find the median
    v.select_nth_unstable(2);

    // We are only guaranteed the slice will be one of the following, based on the way we sort
    // about the specified index.
    assert!(v == [-3, -5, 1, 2, 4] ||
            v == [-5, -3, 1, 2, 4] ||
            v == [-3, -5, 1, 4, 2] ||
            v == [-5, -3, 1, 4, 2]);

Run

#### `pub fn select_nth_unstable_by<F>(
&mut self,
index: usize,
compare: F
) -> (&mut [T], &mut T, &mut [T]) where
F: FnMut(&T, &T) -> Ordering,` 1.49.0[src]

Reorder the slice with a comparator function such that the element at `index` is at its final sorted position.

This reordering has the additional property that any value at position `i < index` will be less than or equal to any value at a position `j > index` using the comparator function. Additionally, this reordering is unstable (i.e. any number of equal elements may end up at position `index`), in-place (i.e. does not allocate), and O(n) worst-case. This function is also known as “kth element” in other libraries. It returns a triplet of the following values: all elements less than the one at the given index, the value at the given index, and all elements greater than the one at the given index, using the provided comparator function.

# Current implementation

The current algorithm is based on the quickselect portion of the same quicksort algorithm used for `sort_unstable`.

# Panics

Panics when `index >= len()`, meaning it always panics on empty slices.

# Examples

    let mut v = [-5i32, 4, 1, -3, 2];

    // Find the median as if the slice were sorted in descending order.
    v.select_nth_unstable_by(2, |a, b| b.cmp(a));

    // We are only guaranteed the slice will be one of the following, based on the way we sort
    // about the specified index.
    assert!(v == [2, 4, 1, -5, -3] ||
            v == [2, 4, 1, -3, -5] ||
            v == [4, 2, 1, -5, -3] ||
            v == [4, 2, 1, -3, -5]);

Run

#### `pub fn select_nth_unstable_by_key<K, F>(
&mut self,
index: usize,
f: F
) -> (&mut [T], &mut T, &mut [T]) where
F: FnMut(&T) -> K,
K: Ord,` 1.49.0[src]

Reorder the slice with a key extraction function such that the element at `index` is at its final sorted position.

This reordering has the additional property that any value at position `i < index` will be less than or equal to any value at a position `j > index` using the key extraction function. Additionally, this reordering is unstable (i.e. any number of equal elements may end up at position `index`), in-place (i.e. does not allocate), and O(n) worst-case. This function is also known as “kth element” in other libraries. It returns a triplet of the following values: all elements less than the one at the given index, the value at the given index, and all elements greater than the one at the given index, using the provided key extraction function.

# Current implementation

The current algorithm is based on the quickselect portion of the same quicksort algorithm used for `sort_unstable`.

# Panics

Panics when `index >= len()`, meaning it always panics on empty slices.

# Examples

    let mut v = [-5i32, 4, 1, -3, 2];

    // Return the median as if the array were sorted according to absolute value.
    v.select_nth_unstable_by_key(2, |a| a.abs());

    // We are only guaranteed the slice will be one of the following, based on the way we sort
    // about the specified index.
    assert!(v == [1, 2, -3, 4, -5] ||
            v == [1, 2, -3, -5, 4] ||
            v == [2, 1, -3, 4, -5] ||
            v == [2, 1, -3, -5, 4]);

Run

#### `pub fn partition_dedup(&mut self) -> (&mut [T], &mut [T]) where
T: PartialEq<T>,` [src]

🔬 This is a nightly-only experimental API. (`slice_partition_dedup` #54279)

Moves all consecutive repeated elements to the end of the slice according to the `PartialEq` trait implementation.

Returns two slices. The first contains no consecutive repeated elements. The second contains all the duplicates in no specified order.

If the slice is sorted, the first returned slice contains no duplicates.

# Examples

    #![feature(slice_partition_dedup)]

    let mut slice = [1, 2, 2, 3, 3, 2, 1, 1];

    let (dedup, duplicates) = slice.partition_dedup();

    assert_eq!(dedup, [1, 2, 3, 2, 1]);
    assert_eq!(duplicates, [2, 3, 1]);

Run

#### `pub fn partition_dedup_by<F>(&mut self, same_bucket: F) -> (&mut [T], &mut [T]) where
F: FnMut(&mut T, &mut T) -> bool,` [src]

🔬 This is a nightly-only experimental API. (`slice_partition_dedup` #54279)

Moves all but the first of consecutive elements to the end of the slice satisfying a given equality relation.

Returns two slices. The first contains no consecutive repeated elements. The second contains all the duplicates in no specified order.

The `same_bucket` function is passed references to two elements from the slice and must determine if the elements compare equal. The elements are passed in opposite order from their order in the slice, so if `same_bucket(a, b)` returns `true`, `a` is moved at the end of the slice.

If the slice is sorted, the first returned slice contains no duplicates.

# Examples

    #![feature(slice_partition_dedup)]

    let mut slice = ["foo", "Foo", "BAZ", "Bar", "bar", "baz", "BAZ"];

    let (dedup, duplicates) = slice.partition_dedup_by(|a, b| a.eq_ignore_ascii_case(b));

    assert_eq!(dedup, ["foo", "BAZ", "Bar", "baz"]);
    assert_eq!(duplicates, ["bar", "Foo", "BAZ"]);

Run

#### `pub fn partition_dedup_by_key<K, F>(&mut self, key: F) -> (&mut [T], &mut [T]) where
F: FnMut(&mut T) -> K,
K: PartialEq<K>,` [src]

🔬 This is a nightly-only experimental API. (`slice_partition_dedup` #54279)

Moves all but the first of consecutive elements to the end of the slice that resolve to the same key.

Returns two slices. The first contains no consecutive repeated elements. The second contains all the duplicates in no specified order.

If the slice is sorted, the first returned slice contains no duplicates.

# Examples

    #![feature(slice_partition_dedup)]

    let mut slice = [10, 20, 21, 30, 30, 20, 11, 13];

    let (dedup, duplicates) = slice.partition_dedup_by_key(|i| *i / 10);

    assert_eq!(dedup, [10, 20, 30, 20, 11]);
    assert_eq!(duplicates, [21, 30, 13]);

Run

#### `pub fn rotate_left(&mut self, mid: usize)`1.26.0[src]

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']);

Run

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']);

Run

#### `pub fn rotate_right(&mut self, k: usize)`1.26.0[src]

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']);

Run

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']);

Run

#### `pub fn fill(&mut self, value: T) where
T: Clone,` 1.50.0[src]

Fills `self` with elements by cloning `value`.

# Examples

    let mut buf = vec![0; 10];
    buf.fill(1);
    assert_eq!(buf, vec![1; 10]);

Run

#### `pub fn fill_with<F>(&mut self, f: F) where
F: FnMut() -> T,` 1.51.0[src]

Fills `self` with elements returned by calling a closure repeatedly.

This method uses a closure to create new values. If you’d rather `Clone` a given value, use `fill`. If you want to use the `Default` trait to generate values, you can pass `Default::default` as the argument.

# Examples

    let mut buf = vec![1; 10];
    buf.fill_with(Default::default);
    assert_eq!(buf, vec![0; 10]);

Run

#### `pub fn clone_from_slice(&mut self, src: &[T]) where
T: Clone,` 1.7.0[src]

Copies the elements from `src` into `self`.

The length of `src` must be the same as `self`.

If `T` 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];

    // Because the slices have to be the same length,
    // we slice the source slice from four elements
    // to two. It will panic if we don't do this.
    dst.clone_from_slice(&src[2..]);

    assert_eq!(src, [1, 2, 3, 4]);
    assert_eq!(dst, [3, 4]);

Run

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:

ⓘ

    let mut slice = [1, 2, 3, 4, 5];

    slice[..2].clone_from_slice(&slice[3..]); // compile fail!

Run

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]);

Run

#### `pub fn copy_from_slice(&mut self, src: &[T]) where
T: Copy,` 1.9.0[src]

Copies all elements from `src` into `self`, using a memcpy.

The length of `src` must be the same as `self`.

If `T` 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];

    // Because the slices have to be the same length,
    // we slice the source slice from four elements
    // to two. It will panic if we don't do this.
    dst.copy_from_slice(&src[2..]);

    assert_eq!(src, [1, 2, 3, 4]);
    assert_eq!(dst, [3, 4]);

Run

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:

ⓘ

    let mut slice = [1, 2, 3, 4, 5];

    slice[..2].copy_from_slice(&slice[3..]); // compile fail!

Run

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]);

Run

#### `pub fn copy_within<R>(&mut self, src: R, dest: usize) where
T: Copy,
R: RangeBounds<usize>,` 1.37.0[src]

Copies elements from one part of the slice to another part of itself, using a memmove.

`src` is the range within `self` to copy from. `dest` is the starting index of the range within `self` to copy to, which will have the same length as `src`. The two ranges may overlap. The ends of the two ranges must be less than or equal to `self.len()`.

# Panics

This function will panic if either range exceeds the end of the slice, or if the end of `src` is before the start.

# Examples

Copying four bytes within a slice:

    let mut bytes = *b"Hello, World!";

    bytes.copy_within(1..5, 8);

    assert_eq!(&bytes, b"Hello, Wello!");

Run

#### `pub fn swap_with_slice(&mut self, other: &mut [T])`1.27.0[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]);

Run

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:

ⓘ

    let mut slice = [1, 2, 3, 4, 5];
    slice[..2].swap_with_slice(&mut slice[3..]); // compile fail!

Run

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]);

Run

#### `pub unsafe fn align_to<U>(&self) -> (&[T], &[U], &[T])`1.30.0[src]

Transmute the slice to a slice of another type, ensuring alignment of the types is maintained.

This method splits the slice into three distinct slices: prefix, correctly aligned middle slice of a new type, and the suffix slice. The method may make the middle slice the greatest length possible for a given type and input slice, but only your algorithm’s performance should depend on that, not its correctness. It is permissible for all of the input data to be returned as the prefix or suffix slice.

This method has no purpose when either input element `T` or output element `U` are zero-sized and will return the original slice without splitting anything.

# Safety

This method is essentially a `transmute` with respect to the elements in the returned middle slice, so all the usual caveats pertaining to `transmute::<T, U>` also apply here.

# Examples

Basic usage:

    unsafe {
        let bytes: [u8; 7] = [1, 2, 3, 4, 5, 6, 7];
        let (prefix, shorts, suffix) = bytes.align_to::<u16>();
        // less_efficient_algorithm_for_bytes(prefix);
        // more_efficient_algorithm_for_aligned_shorts(shorts);
        // less_efficient_algorithm_for_bytes(suffix);
    }

Run

#### `pub unsafe fn align_to_mut<U>(&mut self) -> (&mut [T], &mut [U], &mut [T])`1.30.0[src]

Transmute the slice to a slice of another type, ensuring alignment of the types is maintained.

This method splits the slice into three distinct slices: prefix, correctly aligned middle slice of a new type, and the suffix slice. The method may make the middle slice the greatest length possible for a given type and input slice, but only your algorithm’s performance should depend on that, not its correctness. It is permissible for all of the input data to be returned as the prefix or suffix slice.

This method has no purpose when either input element `T` or output element `U` are zero-sized and will return the original slice without splitting anything.

# Safety

This method is essentially a `transmute` with respect to the elements in the returned middle slice, so all the usual caveats pertaining to `transmute::<T, U>` also apply here.

# Examples

Basic usage:

    unsafe {
        let mut bytes: [u8; 7] = [1, 2, 3, 4, 5, 6, 7];
        let (prefix, shorts, suffix) = bytes.align_to_mut::<u16>();
        // less_efficient_algorithm_for_bytes(prefix);
        // more_efficient_algorithm_for_aligned_shorts(shorts);
        // less_efficient_algorithm_for_bytes(suffix);
    }

Run

#### `pub fn is_sorted(&self) -> bool where
T: PartialOrd<T>,` [src]

🔬 This is a nightly-only experimental API. (`is_sorted` #53485)

new API

Checks if the elements of this slice are sorted.

That is, for each element `a` and its following element `b`, `a <= b` must hold. If the slice yields exactly zero or one element, `true` is returned.

Note that if `Self::Item` is only `PartialOrd`, but not `Ord`, the above definition implies that this function returns `false` if any two consecutive items are not comparable.

# Examples

    #![feature(is_sorted)]
    let empty: [i32; 0] = [];

    assert!([1, 2, 2, 9].is_sorted());
    assert!(![1, 3, 2, 4].is_sorted());
    assert!([0].is_sorted());
    assert!(empty.is_sorted());
    assert!(![0.0, 1.0, f32::NAN].is_sorted());

Run

#### `pub fn is_sorted_by<F>(&self, compare: F) -> bool where
F: FnMut(&T, &T) -> Option<Ordering>,` [src]

🔬 This is a nightly-only experimental API. (`is_sorted` #53485)

new API

Checks if the elements of this slice are sorted using the given comparator function.

Instead of using `PartialOrd::partial_cmp`, this function uses the given `compare` function to determine the ordering of two elements. Apart from that, it’s equivalent to `is_sorted`; see its documentation for more information.

#### `pub fn is_sorted_by_key<F, K>(&self, f: F) -> bool where
F: FnMut(&T) -> K,
K: PartialOrd<K>,` [src]

🔬 This is a nightly-only experimental API. (`is_sorted` #53485)

new API

Checks if the elements of this slice are sorted using the given key extraction function.

Instead of comparing the slice’s elements directly, this function compares the keys of the elements, as determined by `f`. Apart from that, it’s equivalent to `is_sorted`; see its documentation for more information.

# Examples

    #![feature(is_sorted)]

    assert!(["c", "bb", "aaa"].is_sorted_by_key(|s| s.len()));
    assert!(![-2i32, -1, 0, 3].is_sorted_by_key(|n| n.abs()));

Run

#### `pub fn partition_point<P>(&self, pred: P) -> usize where
P: FnMut(&T) -> bool,` 1.52.0[src]

Returns the index of the partition point according to the given predicate (the index of the first element of the second partition).

The slice is assumed to be partitioned according to the given predicate. This means that all elements for which the predicate returns true are at the start of the slice and all elements for which the predicate returns false are at the end. For example, [7, 15, 3, 5, 4, 12, 6] is a partitioned under the predicate x % 2 != 0 (all odd numbers are at the start, all even at the end).

If this slice is not partitioned, the returned result is unspecified and meaningless, as this method performs a kind of binary search.

See also `binary_search`, `binary_search_by`, and `binary_search_by_key`.

# Examples

    let v = [1, 2, 3, 3, 5, 6, 7];
    let i = v.partition_point(|&x| x < 5);

    assert_eq!(i, 4);
    assert!(v[..i].iter().all(|&x| x < 5));
    assert!(v[i..].iter().all(|&x| !(x < 5)));

Run

### `impl [u8]`[src]

#### `pub fn is_ascii(&self) -> bool` 1.23.0[src]

Checks if all bytes in this slice are within the ASCII range.

#### `pub fn eq_ignore_ascii_case(&self, other: &[u8]) -> bool` 1.23.0[src]

Checks that two slices are an ASCII case-insensitive match.

Same as `to_ascii_lowercase(a) == to_ascii_lowercase(b)`, but without allocating and copying temporaries.

#### `pub fn make_ascii_uppercase(&mut self)`1.23.0[src]

Converts this slice to its ASCII upper case equivalent in-place.

ASCII letters ‘a’ to ‘z’ are mapped to ‘A’ to ‘Z’, but non-ASCII letters are unchanged.

To return a new uppercased value without modifying the existing one, use `to_ascii_uppercase`.

#### `pub fn make_ascii_lowercase(&mut self)`1.23.0[src]

Converts this slice to its ASCII lower case equivalent in-place.

ASCII letters ‘A’ to ‘Z’ are mapped to ‘a’ to ‘z’, but non-ASCII letters are unchanged.

To return a new lowercased value without modifying the existing one, use `to_ascii_lowercase`.

#### `pub fn escape_ascii(&self) -> EscapeAscii<'_>ⓘ

### Notable traits for EscapeAscii<'a>

`impl<'a> Iterator for EscapeAscii<'a> type Item = u8;`
`[src]

🔬 This is a nightly-only experimental API. (`inherent_ascii_escape` #77174)

Returns an iterator that produces an escaped version of this slice, treating it as an ASCII string.

# Examples

    #![feature(inherent_ascii_escape)]

    let s = b"0\t\r\n'\"\\\x9d";
    let escaped = s.escape_ascii().to_string();
    assert_eq!(escaped, "0\\t\\r\\n\\'\\\"\\\\\\x9d");

Run

### `impl<T> [T]`[src]

#### `pub fn sort(&mut self) where
T: Ord,` [src]

Sorts the slice.

This sort is stable (i.e., does not reorder equal elements) and O(n * log(n)) worst-case.

When applicable, unstable sorting is preferred because it is generally faster than stable sorting and it doesn’t allocate auxiliary memory. See `sort_unstable`.

# Current implementation

The current algorithm is an adaptive, iterative merge sort inspired by timsort. It is designed to be very fast in cases where the slice is nearly sorted, or consists of two or more sorted sequences concatenated one after another.

Also, it allocates temporary storage half the size of `self`, but for short slices a non-allocating insertion sort is used instead.

# Examples

    let mut v = [-5, 4, 1, -3, 2];

    v.sort();
    assert!(v == [-5, -3, 1, 2, 4]);

Run

#### `pub fn sort_by<F>(&mut self, compare: F) where
F: FnMut(&T, &T) -> Ordering,` [src]

Sorts the slice with a comparator function.

This sort is stable (i.e., does not reorder equal elements) and O(n * log(n)) worst-case.

The comparator function must define a total ordering for the elements in the slice. If the ordering is not total, the order of the elements is unspecified. An order is a total order if it is (for all `a`, `b` and `c`):

- total and antisymmetric: exactly one of `a < b`, `a == b` or `a > b` is true, and
- transitive, `a < b` and `b < c` implies `a < c`. The same must hold for both `==` and `>`.

For example, while `f64` doesn’t implement `Ord` because `NaN != NaN`, we can use `partial_cmp` as our sort function when we know the slice doesn’t contain a `NaN`.

    let mut floats = [5f64, 4.0, 1.0, 3.0, 2.0];
    floats.sort_by(|a, b| a.partial_cmp(b).unwrap());
    assert_eq!(floats, [1.0, 2.0, 3.0, 4.0, 5.0]);

Run

When applicable, unstable sorting is preferred because it is generally faster than stable sorting and it doesn’t allocate auxiliary memory. See `sort_unstable_by`.

# Current implementation

The current algorithm is an adaptive, iterative merge sort inspired by timsort. It is designed to be very fast in cases where the slice is nearly sorted, or consists of two or more sorted sequences concatenated one after another.

Also, it allocates temporary storage half the size of `self`, but for short slices a non-allocating insertion sort is used instead.

# Examples

    let mut v = [5, 4, 1, 3, 2];
    v.sort_by(|a, b| a.cmp(b));
    assert!(v == [1, 2, 3, 4, 5]);

    // reverse sorting
    v.sort_by(|a, b| b.cmp(a));
    assert!(v == [5, 4, 3, 2, 1]);

Run

#### `pub fn sort_by_key<K, F>(&mut self, f: F) where
F: FnMut(&T) -> K,
K: Ord,` 1.7.0[src]

Sorts the slice with a key extraction function.

This sort is stable (i.e., does not reorder equal elements) and O(m * n * log(n)) worst-case, where the key function is O(m).

For expensive key functions (e.g. functions that are not simple property accesses or basic operations), `sort_by_cached_key` is likely to be significantly faster, as it does not recompute element keys.

When applicable, unstable sorting is preferred because it is generally faster than stable sorting and it doesn’t allocate auxiliary memory. See `sort_unstable_by_key`.

# Current implementation

The current algorithm is an adaptive, iterative merge sort inspired by timsort. It is designed to be very fast in cases where the slice is nearly sorted, or consists of two or more sorted sequences concatenated one after another.

Also, it allocates temporary storage half the size of `self`, but for short slices a non-allocating insertion sort is used instead.

# Examples

    let mut v = [-5i32, 4, 1, -3, 2];

    v.sort_by_key(|k| k.abs());
    assert!(v == [1, 2, -3, 4, -5]);

Run

#### `pub fn sort_by_cached_key<K, F>(&mut self, f: F) where
F: FnMut(&T) -> K,
K: Ord,` 1.34.0[src]

Sorts the slice with a key extraction function.

During sorting, the key function is called only once per element.

This sort is stable (i.e., does not reorder equal elements) and O(m * n + n * log(n)) worst-case, where the key function is O(m).

For simple key functions (e.g., functions that are property accesses or basic operations), `sort_by_key` is likely to be faster.

# Current implementation

The current algorithm is based on pattern-defeating quicksort 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.

In the worst case, the algorithm allocates temporary storage in a `Vec<(K, usize)>` the length of the slice.

# Examples

    let mut v = [-5i32, 4, 32, -3, 2];

    v.sort_by_cached_key(|k| k.to_string());
    assert!(v == [-3, -5, 2, 32, 4]);

Run

#### `pub fn to_vec(&self) -> Vec<T, Global>ⓘ

### Notable traits for Vec<u8, A>

`impl<A: Allocator> Write for Vec<u8, A>`
where
T: Clone,` [src]

Copies `self` into a new `Vec`.

# Examples

    let s = [10, 40, 30];
    let x = s.to_vec();
    // Here, `s` and `x` can be modified independently.

Run

#### `pub fn to_vec_in<A>(&self, alloc: A) -> Vec<T, A>ⓘ

### Notable traits for Vec<u8, A>

`impl<A: Allocator> Write for Vec<u8, A>`
where
T: Clone,
A: Allocator,` [src]

🔬 This is a nightly-only experimental API. (`allocator_api` #32838)

Copies `self` into a new `Vec` with an allocator.

# Examples

    #![feature(allocator_api)]

    use std::alloc::System;

    let s = [10, 40, 30];
    let x = s.to_vec_in(System);
    // Here, `s` and `x` can be modified independently.

Run

#### `pub fn into_vec<A>(self: Box<[T], A>) -> Vec<T, A>ⓘ

### Notable traits for Vec<u8, A>

`impl<A: Allocator> Write for Vec<u8, A>`
where
A: Allocator,` [src]

Converts `self` into a vector without clones or allocation.

The resulting vector can be converted back into a box via `Vec<T>`’s `into_boxed_slice` method.

# Examples

    let s: Box<[i32]> = Box::new([10, 40, 30]);
    let x = s.into_vec();
    // `s` cannot be used anymore because it has been converted into `x`.

    assert_eq!(x, vec![10, 40, 30]);

Run

#### `pub fn repeat(&self, n: usize) -> Vec<T, Global>ⓘ

### Notable traits for Vec<u8, A>

`impl<A: Allocator> Write for Vec<u8, A>`
where
T: Copy,` 1.40.0[src]

Creates a vector by repeating a slice `n` times.

# Panics

This function will panic if the capacity would overflow.

# Examples

Basic usage:

    assert_eq!([1, 2].repeat(3), vec![1, 2, 1, 2, 1, 2]);

Run

A panic upon overflow:

ⓘ

    // this will panic at runtime
    b"0123456789abcdef".repeat(usize::MAX);

Run

#### `pub fn concat<Item>(&self) -> <[T] as Concat<Item>>::Outputⓘ

### Notable traits for &[u8]

`impl Read for &[u8]impl Write for &mut [u8]`
where
Item: ?Sized,
[T]: Concat<Item>,` [src]

Flattens a slice of `T` into a single value `Self::Output`.

# Examples

    assert_eq!(["hello", "world"].concat(), "helloworld");
    assert_eq!([[1, 2], [3, 4]].concat(), [1, 2, 3, 4]);

Run

#### `pub fn join<Separator>(
&self,
sep: Separator
) -> <[T] as Join<Separator>>::Outputⓘ

### Notable traits for &[u8]

`impl Read for &[u8]impl Write for &mut [u8]`
where
[T]: Join<Separator>,` 1.3.0[src]

Flattens a slice of `T` into a single value `Self::Output`, placing a given separator between each.

# Examples

    assert_eq!(["hello", "world"].join(" "), "hello world");
    assert_eq!([[1, 2], [3, 4]].join(&0), [1, 2, 0, 3, 4]);
    assert_eq!([[1, 2], [3, 4]].join(&[0, 0][..]), [1, 2, 0, 0, 3, 4]);

Run

#### `pub fn connect<Separator>(
&self,
sep: Separator
) -> <[T] as Join<Separator>>::Outputⓘ

### Notable traits for &[u8]

`impl Read for &[u8]impl Write for &mut [u8]`
where
[T]: Join<Separator>,` [src]

👎 Deprecated since 1.3.0:

renamed to join

Flattens a slice of `T` into a single value `Self::Output`, placing a given separator between each.

# Examples

    assert_eq!(["hello", "world"].connect(" "), "hello world");
    assert_eq!([[1, 2], [3, 4]].connect(&0), [1, 2, 0, 3, 4]);

Run

### `impl [u8]`[src]

#### `pub fn to_ascii_uppercase(&self) -> Vec<u8, Global>ⓘ

### Notable traits for Vec<u8, A>

`impl<A: Allocator> Write for Vec<u8, A>`
`1.23.0[src]

Returns a vector containing a copy of this slice where each byte is mapped to its ASCII upper case equivalent.

ASCII letters ‘a’ to ‘z’ are mapped to ‘A’ to ‘Z’, but non-ASCII letters are unchanged.

To uppercase the value in-place, use `make_ascii_uppercase`.

#### `pub fn to_ascii_lowercase(&self) -> Vec<u8, Global>ⓘ

### Notable traits for Vec<u8, A>

`impl<A: Allocator> Write for Vec<u8, A>`
`1.23.0[src]

Returns a vector containing a copy of this slice where each byte is mapped to its ASCII lower case equivalent.

ASCII letters ‘A’ to ‘Z’ are mapped to ‘a’ to ‘z’, but non-ASCII letters are unchanged.

To lowercase the value in-place, use `make_ascii_lowercase`.

## Trait Implementations

### `impl<T> AsMut<[T]> for [T]`[src]

#### `pub fn as_mut(&mut self) -> &mut [T]ⓘ

### Notable traits for &[u8]

`impl Read for &[u8]impl Write for &mut [u8]`
`[src]

Performs the conversion.

### `impl<T> AsRef<[T]> for [T]`[src]

#### `pub fn as_ref(&self) -> &[T]ⓘ

### Notable traits for &[u8]

`impl Read for &[u8]impl Write for &mut [u8]`
`[src]

Performs the conversion.

### `impl AsciiExt for [u8]`[src]

#### `type Owned = Vec<u8>`

👎 Deprecated since 1.26.0:

use inherent methods instead

Container type for copied ASCII characters.

#### `fn is_ascii(&self) -> bool`[src]

👎 Deprecated since 1.26.0:

use inherent methods instead

Checks if the value is within the ASCII range. Read more

#### `fn to_ascii_uppercase(&self) -> Self::Owned`[src]

👎 Deprecated since 1.26.0:

use inherent methods instead

Makes a copy of the value in its ASCII upper case equivalent. Read more

#### `fn to_ascii_lowercase(&self) -> Self::Owned`[src]

👎 Deprecated since 1.26.0:

use inherent methods instead

Makes a copy of the value in its ASCII lower case equivalent. Read more

#### `fn eq_ignore_ascii_case(&self, o: &Self) -> bool`[src]

👎 Deprecated since 1.26.0:

use inherent methods instead

Checks that two values are an ASCII case-insensitive match. Read more

#### `fn make_ascii_uppercase(&mut self)`[src]

👎 Deprecated since 1.26.0:

use inherent methods instead

Converts this type to its ASCII upper case equivalent in-place. Read more

#### `fn make_ascii_lowercase(&mut self)`[src]

👎 Deprecated since 1.26.0:

use inherent methods instead

Converts this type to its ASCII lower case equivalent in-place. Read more

### `impl BufRead for &[u8]`[src]

#### `fn fill_buf(&mut self) -> Result<&[u8]>`[src]

Returns the contents of the internal buffer, filling it with more data from the inner reader if it is empty. Read more

#### `fn consume(&mut self, amt: usize)`[src]

Tells this buffer that `amt` bytes have been consumed from the buffer, so they should no longer be returned in calls to `read`. Read more

#### `fn read_until(&mut self, byte: u8, buf: &mut Vec<u8>) -> Result<usize>`[src]

Read all bytes into `buf` until the delimiter `byte` or EOF is reached. Read more

#### `fn read_line(&mut self, buf: &mut String) -> Result<usize>`[src]

Read all bytes until a newline (the `0xA` byte) is reached, and append them to the provided buffer. Read more

#### `fn split(self, byte: u8) -> Split<Self>ⓘ

### Notable traits for Split<B>

`impl<B: BufRead> Iterator for Split<B> type Item = Result<Vec<u8>>;`
where
Self: Sized,` [src]

Returns an iterator over the contents of this reader split on the byte `byte`. Read more

#### `fn lines(self) -> Lines<Self>ⓘ

### Notable traits for Lines<B>

`impl<B: BufRead> Iterator for Lines<B> type Item = Result<String>;`
where
Self: Sized,` [src]

Returns an iterator over the lines of this reader. Read more

### `impl<T, V> Concat<T> for [V] where
T: Clone,
V: Borrow<[T]>,` [src]

#### `type Output = Vec<T, Global>`

🔬 This is a nightly-only experimental API. (`slice_concat_trait` #27747)

The resulting type after concatenation

#### `pub fn concat(slice: &[V]) -> Vec<T, Global>ⓘ

### Notable traits for Vec<u8, A>

`impl<A: Allocator> Write for Vec<u8, A>`
`[src]

🔬 This is a nightly-only experimental API. (`slice_concat_trait` #27747)

Implementation of `[T]::concat`

### `impl<S> Concat<str> for [S] where
S: Borrow<str>,` [src]

Note: `str` in `Concat<str>` is not meaningful here. This type parameter of the trait only exists to enable another impl.

#### `type Output = String`

🔬 This is a nightly-only experimental API. (`slice_concat_trait` #27747)

The resulting type after concatenation

#### `pub fn concat(slice: &[S]) -> String`[src]

🔬 This is a nightly-only experimental API. (`slice_concat_trait` #27747)

Implementation of `[T]::concat`

### `impl<T> Debug for [T] where
T: Debug,` [src]

#### `pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

Formats the value using the given formatter. Read more

### `impl<'_, T> Default for &'_ mut [T]`1.5.0[src]

#### `pub fn default() -> &'_ mut [T]ⓘ

### Notable traits for &[u8]

`impl Read for &[u8]impl Write for &mut [u8]`
`[src]

Creates a mutable empty slice.

### `impl<'_, T> Default for &'_ [T]`[src]

#### `pub fn default() -> &'_ [T]ⓘ

### Notable traits for &[u8]

`impl Read for &[u8]impl Write for &mut [u8]`
`[src]

Creates an empty slice.

### `impl<T> Hash for [T] where
T: Hash,` [src]

#### `pub fn hash<H>(&self, state: &mut H) where
H: Hasher,` [src]

Feeds this value into the given `Hasher`. Read more

#### `pub fn hash_slice<H>(data: &[Self], state: &mut H) where
H: Hasher,` 1.3.0[src]

Feeds a slice of this type into the given `Hasher`. Read more

### `impl<T, I> Index<I> for [T] where
I: SliceIndex<[T]>,` [src]

#### `type Output = <I as SliceIndex<[T]>>::Output`

The returned type after indexing.

#### `pub fn index(&self, index: I) -> &<I as SliceIndex<[T]>>::Output`[src]

Performs the indexing (`container[index]`) operation. Read more

### `impl<T, I> IndexMut<I> for [T] where
I: SliceIndex<[T]>,` [src]

#### `pub fn index_mut(&mut self, index: I) -> &mut <I as SliceIndex<[T]>>::Output`[src]

Performs the mutable indexing (`container[index]`) operation. Read more

### `impl<'a, T> IntoIterator for &'a [T]`[src]

#### `type Item = &'a T`

The type of the elements being iterated over.

#### `type IntoIter = Iter<'a, T>`

Which kind of iterator are we turning this into?

#### `pub fn into_iter(self) -> Iter<'a, T>ⓘ

### Notable traits for Iter<'a, T>

`impl<'a, T> Iterator for Iter<'a, T> type Item = &'a T;`
`[src]

Creates an iterator from a value. Read more

### `impl<'a, T> IntoIterator for &'a mut [T]`[src]

#### `type Item = &'a mut T`

The type of the elements being iterated over.

#### `type IntoIter = IterMut<'a, T>`

Which kind of iterator are we turning this into?

#### `pub fn into_iter(self) -> IterMut<'a, T>ⓘ

### Notable traits for IterMut<'a, T>

`impl<'a, T> Iterator for IterMut<'a, T> type Item = &'a mut T;`
`[src]

Creates an iterator from a value. Read more

### `impl<'_, T, V> Join<&'_ [T]> for [V] where
T: Clone,
V: Borrow<[T]>,` [src]

#### `type Output = Vec<T, Global>`

🔬 This is a nightly-only experimental API. (`slice_concat_trait` #27747)

The resulting type after concatenation

#### `pub fn join(slice: &[V], sep: &[T]) -> Vec<T, Global>ⓘ

### Notable traits for Vec<u8, A>

`impl<A: Allocator> Write for Vec<u8, A>`
`[src]

🔬 This is a nightly-only experimental API. (`slice_concat_trait` #27747)

Implementation of `[T]::join`

### `impl<'_, T, V> Join<&'_ T> for [V] where
T: Clone,
V: Borrow<[T]>,` [src]

#### `type Output = Vec<T, Global>`

🔬 This is a nightly-only experimental API. (`slice_concat_trait` #27747)

The resulting type after concatenation

#### `pub fn join(slice: &[V], sep: &T) -> Vec<T, Global>ⓘ

### Notable traits for Vec<u8, A>

`impl<A: Allocator> Write for Vec<u8, A>`
`[src]

🔬 This is a nightly-only experimental API. (`slice_concat_trait` #27747)

Implementation of `[T]::join`

### `impl<'_, S> Join<&'_ str> for [S] where
S: Borrow<str>,` [src]

#### `type Output = String`

🔬 This is a nightly-only experimental API. (`slice_concat_trait` #27747)

The resulting type after concatenation

#### `pub fn join(slice: &[S], sep: &str) -> String`[src]

🔬 This is a nightly-only experimental API. (`slice_concat_trait` #27747)

Implementation of `[T]::join`

### `impl<T> Ord for [T] where
T: Ord,` [src]

Implements comparison of vectors lexicographically.

#### `pub fn cmp(&self, other: &[T]) -> Ordering`[src]

This method returns an `Ordering` between `self` and `other`. Read more

#### `
#[must_use]
pub fn max(self, other: Self) -> Self` 1.21.0[src]

Compares and returns the maximum of two values. Read more

#### `
#[must_use]
pub fn min(self, other: Self) -> Self` 1.21.0[src]

Compares and returns the minimum of two values. Read more

#### `
#[must_use]
pub fn clamp(self, min: Self, max: Self) -> Self` 1.50.0[src]

Restrict a value to a certain interval. Read more

### `impl<A, B, const N: usize> PartialEq<[A; N]> for [B] where
B: PartialEq<A>,` [src]

#### `pub fn eq(&self, other: &[A; N]) -> bool`[src]

This method tests for `self` and `other` values to be equal, and is used by `==`. Read more

#### `pub fn ne(&self, other: &[A; N]) -> bool`[src]

This method tests for `!=`.

### `impl<'_, A, B, const N: usize> PartialEq<[A; N]> for &'_ mut [B] where
B: PartialEq<A>,` [src]

#### `pub fn eq(&self, other: &[A; N]) -> bool`[src]

This method tests for `self` and `other` values to be equal, and is used by `==`. Read more

#### `pub fn ne(&self, other: &[A; N]) -> bool`[src]

This method tests for `!=`.

### `impl<'_, A, B, const N: usize> PartialEq<[A; N]> for &'_ [B] where
B: PartialEq<A>,` [src]

#### `pub fn eq(&self, other: &[A; N]) -> bool`[src]

This method tests for `self` and `other` values to be equal, and is used by `==`. Read more

#### `pub fn ne(&self, other: &[A; N]) -> bool`[src]

This method tests for `!=`.

### `impl<A, B> PartialEq<[B]> for [A] where
A: PartialEq<B>,` [src]

#### `pub fn eq(&self, other: &[B]) -> bool`[src]

This method tests for `self` and `other` values to be equal, and is used by `==`. Read more

#### `pub fn ne(&self, other: &[B]) -> bool`[src]

This method tests for `!=`.

### `impl<'_, T, U, A> PartialEq<Vec<U, A>> for &'_ mut [T] where
T: PartialEq<U>,
A: Allocator,` 1.46.0[src]

#### `pub fn eq(&self, other: &Vec<U, A>) -> bool`[src]

This method tests for `self` and `other` values to be equal, and is used by `==`. Read more

#### `pub fn ne(&self, other: &Vec<U, A>) -> bool`[src]

This method tests for `!=`.

### `impl<T, U, A> PartialEq<Vec<U, A>> for [T] where
T: PartialEq<U>,
A: Allocator,` 1.48.0[src]

#### `pub fn eq(&self, other: &Vec<U, A>) -> bool`[src]

This method tests for `self` and `other` values to be equal, and is used by `==`. Read more

#### `pub fn ne(&self, other: &Vec<U, A>) -> bool`[src]

This method tests for `!=`.

### `impl<'_, T, U, A> PartialEq<Vec<U, A>> for &'_ [T] where
T: PartialEq<U>,
A: Allocator,` 1.46.0[src]

#### `pub fn eq(&self, other: &Vec<U, A>) -> bool`[src]

This method tests for `self` and `other` values to be equal, and is used by `==`. Read more

#### `pub fn ne(&self, other: &Vec<U, A>) -> bool`[src]

This method tests for `!=`.

### `impl<T> PartialOrd<[T]> for [T] where
T: PartialOrd<T>,` [src]

Implements comparison of vectors lexicographically.

#### `pub fn partial_cmp(&self, other: &[T]) -> Option<Ordering>`[src]

This method returns an ordering between `self` and `other` values if one exists. Read more

#### `
#[must_use]
pub fn lt(&self, other: &Rhs) -> bool`[src]

This method tests less than (for `self` and `other`) and is used by the `<` operator. Read more

#### `
#[must_use]
pub fn le(&self, other: &Rhs) -> bool`[src]

This method tests less than or equal to (for `self` and `other`) and is used by the `<=` operator. Read more

#### `
#[must_use]
pub fn gt(&self, other: &Rhs) -> bool`[src]

This method tests greater than (for `self` and `other`) and is used by the `>` operator. Read more

#### `
#[must_use]
pub fn ge(&self, other: &Rhs) -> bool`[src]

This method tests greater than or equal to (for `self` and `other`) and is used by the `>=` operator. Read more

### `impl<'a, 'b> Pattern<'a> for &'b [char]`[src]

Searches for chars that are equal to any of the `char`s in the slice.

# Examples

    assert_eq!("Hello world".find(&['l', 'l'] as &[_]), Some(2));
    assert_eq!("Hello world".find(&['l', 'l'][..]), Some(2));

Run

#### `type Searcher = CharSliceSearcher<'a, 'b>`

🔬 This is a nightly-only experimental API. (`pattern` #27721)

API not fully fleshed out and ready to be stabilized

Associated searcher for this pattern

#### `pub fn into_searcher(self, haystack: &'a str) -> CharSliceSearcher<'a, 'b>`[src]

🔬 This is a nightly-only experimental API. (`pattern` #27721)

API not fully fleshed out and ready to be stabilized

Constructs the associated searcher from `self` and the `haystack` to search in. Read more

#### `pub fn is_contained_in(self, haystack: &'a str) -> bool`[src]

🔬 This is a nightly-only experimental API. (`pattern` #27721)

API not fully fleshed out and ready to be stabilized

Checks whether the pattern matches anywhere in the haystack

#### `pub fn is_prefix_of(self, haystack: &'a str) -> bool`[src]

🔬 This is a nightly-only experimental API. (`pattern` #27721)

API not fully fleshed out and ready to be stabilized

Checks whether the pattern matches at the front of the haystack

#### `pub fn strip_prefix_of(self, haystack: &'a str) -> Option<&'a str>`[src]

🔬 This is a nightly-only experimental API. (`pattern` #27721)

API not fully fleshed out and ready to be stabilized

Removes the pattern from the front of haystack, if it matches.

#### `pub fn is_suffix_of(self, haystack: &'a str) -> bool where
CharSliceSearcher<'a, 'b>: ReverseSearcher<'a>,` [src]

🔬 This is a nightly-only experimental API. (`pattern` #27721)

API not fully fleshed out and ready to be stabilized

Checks whether the pattern matches at the back of the haystack

#### `pub fn strip_suffix_of(self, haystack: &'a str) -> Option<&'a str> where
CharSliceSearcher<'a, 'b>: ReverseSearcher<'a>,` [src]

🔬 This is a nightly-only experimental API. (`pattern` #27721)

API not fully fleshed out and ready to be stabilized

Removes the pattern from the back of haystack, if it matches.

### `impl Read for &[u8]`[src]

Read is implemented for `&[u8]` by copying from the slice.

Note that reading updates the slice to point to the yet unread part. The slice will be empty when EOF is reached.

#### `fn read(&mut self, buf: &mut [u8]) -> Result<usize>`[src]

Pull some bytes from this source into the specified buffer, returning how many bytes were read. Read more

#### `fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> Result<usize>`[src]

Like `read`, except that it reads into a slice of buffers. Read more

#### `fn is_read_vectored(&self) -> bool`[src]

🔬 This is a nightly-only experimental API. (`can_vector` #69941)

Determines if this `Read`er has an efficient `read_vectored` implementation. Read more

#### `unsafe fn initializer(&self) -> Initializer`[src]

🔬 This is a nightly-only experimental API. (`read_initializer` #42788)

Determines if this `Read`er can work with buffers of uninitialized memory. Read more

#### `fn read_exact(&mut self, buf: &mut [u8]) -> Result<()>`[src]

Read the exact number of bytes required to fill `buf`. Read more

#### `fn read_to_end(&mut self, buf: &mut Vec<u8>) -> Result<usize>`[src]

Read all bytes until EOF in this source, placing them into `buf`. Read more

#### `fn read_to_string(&mut self, buf: &mut String) -> Result<usize>`[src]

Read all bytes until EOF in this source, appending them to `buf`. Read more

#### `fn by_ref(&mut self) -> &mut Selfⓘ

### Notable traits for &'_ mut I

`impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized, type Item = <I as Iterator>::Item;impl<'_, F> Future for &'_ mut F where
F: Future + Unpin + ?Sized, type Output = <F as Future>::Output;impl<R: Read + ?Sized> Read for &mut Rimpl<W: Write + ?Sized> Write for &mut W`
where
Self: Sized,` [src]

Creates a “by reference” adaptor for this instance of `Read`. Read more

#### `fn bytes(self) -> Bytes<Self>ⓘ

### Notable traits for Bytes<R>

`impl<R: Read> Iterator for Bytes<R> type Item = Result<u8>;`
where
Self: Sized,` [src]

Transforms this `Read` instance to an `Iterator` over its bytes. Read more

#### `fn chain<R: Read>(self, next: R) -> Chain<Self, R>ⓘ

### Notable traits for Chain<T, U>

`impl<T: Read, U: Read> Read for Chain<T, U>`
where
Self: Sized,` [src]

Creates an adaptor which will chain this stream with another. Read more

#### `fn take(self, limit: u64) -> Take<Self>ⓘ

### Notable traits for Take<T>

`impl<T: Read> Read for Take<T>`
where
Self: Sized,` [src]

Creates an adaptor which will read at most `limit` bytes from it. Read more

### `impl<T> SlicePattern for [T]`1.51.0[src]

#### `type Item = T`

🔬 This is a nightly-only experimental API. (`slice_pattern` #56345)

stopgap trait for slice patterns

The element type of the slice being matched on.

#### `pub fn as_slice(&self) -> &[<[T] as SlicePattern>::Item]ⓘ

### Notable traits for &[u8]

`impl Read for &[u8]impl Write for &mut [u8]`
`[src]

🔬 This is a nightly-only experimental API. (`slice_pattern` #56345)

stopgap trait for slice patterns

Currently, the consumers of `SlicePattern` need a slice.

### `impl<T> ToOwned for [T] where
T: Clone,` [src]

#### `type Owned = Vec<T, Global>`

The resulting type after obtaining ownership.

#### `pub fn to_owned(&self) -> Vec<T, Global>ⓘ

### Notable traits for Vec<u8, A>

`impl<A: Allocator> Write for Vec<u8, A>`
`[src]

Creates owned data from borrowed data, usually by cloning. Read more

#### `pub fn clone_into(&self, target: &mut Vec<T, Global>)`[src]

🔬 This is a nightly-only experimental API. (`toowned_clone_into` #41263)

recently added

Uses borrowed data to replace owned data, usually by cloning. Read more

### `impl<'a> ToSocketAddrs for &'a [SocketAddr]`1.8.0[src]

#### `type Iter = Cloned<Iter<'a, SocketAddr>>`

Returned iterator over socket addresses which this type may correspond to. Read more

#### `fn to_socket_addrs(&self) -> Result<Self::Iter>`[src]

Converts this object to an iterator of resolved `SocketAddr`s. Read more

### `impl Write for &mut [u8]`[src]

Write is implemented for `&mut [u8]` by copying into the slice, overwriting its data.

Note that writing updates the slice to point to the yet unwritten part. The slice will be empty when it has been completely overwritten.

If the number of bytes to be written exceeds the size of the slice, write operations will return short writes: ultimately, `Ok(0)`; in this situation, `write_all` returns an error of kind `ErrorKind::WriteZero`.

#### `fn write(&mut self, data: &[u8]) -> Result<usize>`[src]

Write a buffer into this writer, returning how many bytes were written. Read more

#### `fn write_vectored(&mut self, bufs: &[IoSlice<'_>]) -> Result<usize>`[src]

Like `write`, except that it writes from a slice of buffers. Read more

#### `fn is_write_vectored(&self) -> bool`[src]

🔬 This is a nightly-only experimental API. (`can_vector` #69941)

Determines if this `Write`r has an efficient `write_vectored` implementation. Read more

#### `fn write_all(&mut self, data: &[u8]) -> Result<()>`[src]

Attempts to write an entire buffer into this writer. Read more

#### `fn flush(&mut self) -> Result<()>`[src]

Flush this output stream, ensuring that all intermediately buffered contents reach their destination. Read more

#### `fn write_all_vectored(&mut self, bufs: &mut [IoSlice<'_>]) -> Result<()>`[src]

🔬 This is a nightly-only experimental API. (`write_all_vectored` #70436)

Attempts to write multiple buffers into this writer. Read more

#### `fn write_fmt(&mut self, fmt: Arguments<'_>) -> Result<()>`[src]

Writes a formatted string into this writer, returning any error encountered. Read more

#### `fn by_ref(&mut self) -> &mut Selfⓘ

### Notable traits for &'_ mut I

`impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized, type Item = <I as Iterator>::Item;impl<'_, F> Future for &'_ mut F where
F: Future + Unpin + ?Sized, type Output = <F as Future>::Output;impl<R: Read + ?Sized> Read for &mut Rimpl<W: Write + ?Sized> Write for &mut W`
where
Self: Sized,` [src]

Creates a “by reference” adaptor for this instance of `Write`. Read more

### `impl<T> Eq for [T] where
T: Eq,` [src]

## Auto Trait Implementations

### `impl<T> RefUnwindSafe for [T] where
T: RefUnwindSafe,`

### `impl RefUnwindSafe for [u8]`

### `impl<T> Send for [T] where
T: Send,`

### `impl Send for [u8]`

### `impl<T> !Sized for [T]`

### `impl !Sized for [u8]`

### `impl<T> Sync for [T] where
T: Sync,`

### `impl Sync for [u8]`

### `impl<T> Unpin for [T] where
T: Unpin,`

### `impl Unpin for [u8]`

### `impl<T> UnwindSafe for [T] where
T: UnwindSafe,`

### `impl UnwindSafe for [u8]`

## Blanket Implementations

### `impl<T> Any for T where
T: 'static + ?Sized,` [src]

#### `pub fn type_id(&self) -> TypeId`[src]

Gets the `TypeId` of `self`. Read more

### `impl<T> Any for T where
T: 'static + ?Sized,` [src]

#### `pub fn type_id(&self) -> TypeId`[src]

Gets the `TypeId` of `self`. Read more

### `impl<T> Borrow<T> for T where
T: ?Sized,` [src]

#### `pub fn borrow(&self) -> &Tⓘ

### Notable traits for &'_ mut I

`impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized, type Item = <I as Iterator>::Item;impl<'_, F> Future for &'_ mut F where
F: Future + Unpin + ?Sized, type Output = <F as Future>::Output;impl<R: Read + ?Sized> Read for &mut Rimpl<W: Write + ?Sized> Write for &mut W`
`[src]

Immutably borrows from an owned value. Read more

### `impl<T> Borrow<T> for T where
T: ?Sized,` [src]

#### `pub fn borrow(&self) -> &Tⓘ

### Notable traits for &'_ mut I

`impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized, type Item = <I as Iterator>::Item;impl<'_, F> Future for &'_ mut F where
F: Future + Unpin + ?Sized, type Output = <F as Future>::Output;impl<R: Read + ?Sized> Read for &mut Rimpl<W: Write + ?Sized> Write for &mut W`
`[src]

Immutably borrows from an owned value. Read more

### `impl<T> BorrowMut<T> for T where
T: ?Sized,` [src]

#### `pub fn borrow_mut(&mut self) -> &mut Tⓘ

### Notable traits for &'_ mut I

`impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized, type Item = <I as Iterator>::Item;impl<'_, F> Future for &'_ mut F where
F: Future + Unpin + ?Sized, type Output = <F as Future>::Output;impl<R: Read + ?Sized> Read for &mut Rimpl<W: Write + ?Sized> Write for &mut W`
`[src]

Mutably borrows from an owned value. Read more

### `impl<T> BorrowMut<T> for T where
T: ?Sized,` [src]

#### `pub fn borrow_mut(&mut self) -> &mut Tⓘ

### Notable traits for &'_ mut I

`impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized, type Item = <I as Iterator>::Item;impl<'_, F> Future for &'_ mut F where
F: Future + Unpin + ?Sized, type Output = <F as Future>::Output;impl<R: Read + ?Sized> Read for &mut Rimpl<W: Write + ?Sized> Write for &mut W`
`[src]

Mutably borrows from an owned value. Read more