#[repr(transparent)]pub struct IoSlice<'a>(_);
Expand description
A buffer type used with Write::write_vectored
.
It is semantically a wrapper around a &[u8]
, but is guaranteed to be
ABI compatible with the iovec
type on Unix platforms and WSABUF
on
Windows.
Implementations
sourceimpl<'a> IoSlice<'a>
impl<'a> IoSlice<'a>
sourcepub fn new(buf: &'a [u8]) -> IoSlice<'a>
pub fn new(buf: &'a [u8]) -> IoSlice<'a>
Creates a new IoSlice
wrapping a byte slice.
Panics
Panics on Windows if the slice is larger than 4GB.
sourcepub fn advance(&mut self, n: usize)
pub fn advance(&mut self, n: usize)
Advance the internal cursor of the slice.
Also see IoSlice::advance_slices
to advance the cursors of multiple
buffers.
Panics
Panics when trying to advance beyond the end of the slice.
Examples
#![feature(io_slice_advance)]
use std::io::IoSlice;
use std::ops::Deref;
let data = [1; 8];
let mut buf = IoSlice::new(&data);
// Mark 3 bytes as read.
buf.advance(3);
assert_eq!(buf.deref(), [1; 5].as_ref());
Runsourcepub fn advance_slices(bufs: &mut &mut [IoSlice<'a>], n: usize)
pub fn advance_slices(bufs: &mut &mut [IoSlice<'a>], n: usize)
Advance a slice of slices.
Shrinks the slice to remove any IoSlice
s that are fully advanced over.
If the cursor ends up in the middle of an IoSlice
, it is modified
to start at that cursor.
For example, if we have a slice of two 8-byte IoSlice
s, and we advance by 10 bytes,
the result will only include the second IoSlice
, advanced by 2 bytes.
Panics
Panics when trying to advance beyond the end of the slices.
Examples
#![feature(io_slice_advance)]
use std::io::IoSlice;
use std::ops::Deref;
let buf1 = [1; 8];
let buf2 = [2; 16];
let buf3 = [3; 8];
let mut bufs = &mut [
IoSlice::new(&buf1),
IoSlice::new(&buf2),
IoSlice::new(&buf3),
][..];
// Mark 10 bytes as written.
IoSlice::advance_slices(&mut bufs, 10);
assert_eq!(bufs[0].deref(), [2; 14].as_ref());
assert_eq!(bufs[1].deref(), [3; 8].as_ref());
RunMethods from Deref<Target = [u8]>
1.5.0 · sourcepub fn split_first(&self) -> Option<(&T, &[T])>
pub fn split_first(&self) -> Option<(&T, &[T])>
1.5.0 · sourcepub fn split_last(&self) -> Option<(&T, &[T])>
pub fn split_last(&self) -> Option<(&T, &[T])>
1.0.0 · sourcepub fn get<I>(&self, index: I) -> Option<&<I as SliceIndex<[T]>>::Output> where
I: SliceIndex<[T]>,
pub fn get<I>(&self, index: I) -> Option<&<I as SliceIndex<[T]>>::Output> where
I: SliceIndex<[T]>,
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));
Run1.0.0 · sourcepub unsafe fn get_unchecked<I>(
&self,
index: I
) -> &<I as SliceIndex<[T]>>::Output where
I: SliceIndex<[T]>,
pub unsafe fn get_unchecked<I>(
&self,
index: I
) -> &<I as SliceIndex<[T]>>::Output where
I: SliceIndex<[T]>,
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);
}
Run1.0.0 · sourcepub fn as_ptr(&self) -> *const T
pub fn as_ptr(&self) -> *const T
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));
}
}
Run1.48.0 · sourcepub 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;
pub 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;
A: Step, type Item = A;
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));
Run1.0.0 · sourcepub fn iter(&self) -> Iter<'_, T>ⓘNotable traits for Iter<'a, T>impl<'a, T> Iterator for Iter<'a, T> type Item = &'a T;
pub fn iter(&self) -> Iter<'_, T>ⓘNotable traits for Iter<'a, T>impl<'a, T> Iterator for Iter<'a, T> type Item = &'a T;
1.0.0 · sourcepub 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];
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];
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());
RunIf the slice is shorter than size
:
let slice = ['f', 'o', 'o'];
let mut iter = slice.windows(4);
assert!(iter.next().is_none());
Run1.0.0 · sourcepub 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];
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];
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());
Run1.31.0 · sourcepub 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];
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];
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']);
Runsourcepub unsafe fn as_chunks_unchecked<const N: usize>(&self) -> &[[T; N]]
pub unsafe fn as_chunks_unchecked<const N: usize>(&self) -> &[[T; N]]
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 (akaself.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
Runsourcepub fn as_chunks<const N: usize>(&self) -> (&[[T; N]], &[T])
pub fn as_chunks<const N: usize>(&self) -> (&[[T; N]], &[T])
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']);
Runsourcepub fn as_rchunks<const N: usize>(&self) -> (&[T], &[[T; N]])
pub fn as_rchunks<const N: usize>(&self) -> (&[T], &[[T; N]])
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']]);
Runsourcepub 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];
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];
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']);
Runsourcepub 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];
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];
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());
Run1.31.0 · sourcepub 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];
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];
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());
Run1.31.0 · sourcepub 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];
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];
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']);
Runsourcepub 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,
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,
T: 'a,
P: FnMut(&T, &T) -> bool, type Item = &'a [T];
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);
RunThis 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);
Run1.0.0 · sourcepub fn split_at(&self, mid: usize) -> (&[T], &[T])
pub fn split_at(&self, mid: usize) -> (&[T], &[T])
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, []);
}
Runsourcepub unsafe fn split_at_unchecked(&self, mid: usize) -> (&[T], &[T])
pub unsafe fn split_at_unchecked(&self, mid: usize) -> (&[T], &[T])
Divides one slice into two at an index, without doing bounds checking.
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).
For a safe alternative see split_at
.
Safety
Calling this method with an out-of-bounds index is undefined behavior
even if the resulting reference is not used. The caller has to ensure that
0 <= mid <= self.len()
.
Examples
#![feature(slice_split_at_unchecked)]
let v = [1, 2, 3, 4, 5, 6];
unsafe {
let (left, right) = v.split_at_unchecked(0);
assert_eq!(left, []);
assert_eq!(right, [1, 2, 3, 4, 5, 6]);
}
unsafe {
let (left, right) = v.split_at_unchecked(2);
assert_eq!(left, [1, 2]);
assert_eq!(right, [3, 4, 5, 6]);
}
unsafe {
let (left, right) = v.split_at_unchecked(6);
assert_eq!(left, [1, 2, 3, 4, 5, 6]);
assert_eq!(right, []);
}
Runsourcepub fn split_array_ref<const N: usize>(&self) -> (&[T; N], &[T])
pub fn split_array_ref<const N: usize>(&self) -> (&[T; N], &[T])
Divides one slice into an array and a remainder slice at an index.
The array will contain all indices from [0, N)
(excluding
the index N
itself) and the slice will contain all
indices from [N, len)
(excluding the index len
itself).
Panics
Panics if N > len
.
Examples
#![feature(split_array)]
let v = &[1, 2, 3, 4, 5, 6][..];
{
let (left, right) = v.split_array_ref::<0>();
assert_eq!(left, &[]);
assert_eq!(right, [1, 2, 3, 4, 5, 6]);
}
{
let (left, right) = v.split_array_ref::<2>();
assert_eq!(left, &[1, 2]);
assert_eq!(right, [3, 4, 5, 6]);
}
{
let (left, right) = v.split_array_ref::<6>();
assert_eq!(left, &[1, 2, 3, 4, 5, 6]);
assert_eq!(right, []);
}
Runsourcepub fn rsplit_array_ref<const N: usize>(&self) -> (&[T], &[T; N])
pub fn rsplit_array_ref<const N: usize>(&self) -> (&[T], &[T; N])
Divides one slice into an array and a remainder slice at an index from the end.
The slice will contain all indices from [0, len - N)
(excluding
the index len - N
itself) and the array will contain all
indices from [len - N, len)
(excluding the index len
itself).
Panics
Panics if N > len
.
Examples
#![feature(split_array)]
let v = &[1, 2, 3, 4, 5, 6][..];
{
let (left, right) = v.rsplit_array_ref::<0>();
assert_eq!(left, [1, 2, 3, 4, 5, 6]);
assert_eq!(right, &[]);
}
{
let (left, right) = v.rsplit_array_ref::<2>();
assert_eq!(left, [1, 2, 3, 4]);
assert_eq!(right, &[5, 6]);
}
{
let (left, right) = v.rsplit_array_ref::<6>();
assert_eq!(left, []);
assert_eq!(right, &[1, 2, 3, 4, 5, 6]);
}
Run1.0.0 · sourcepub 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,
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,
P: FnMut(&T) -> bool, type Item = &'a [T];
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());
RunIf 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());
RunIf 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());
Run1.51.0 · sourcepub 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,
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,
P: FnMut(&T) -> bool, type Item = &'a [T];
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());
RunIf 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());
Run1.27.0 · sourcepub 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,
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,
P: FnMut(&T) -> bool, type Item = &'a [T];
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);
RunAs 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);
Run1.0.0 · sourcepub 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,
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,
P: FnMut(&T) -> bool, type Item = &'a [T];
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:?}");
}
Run1.0.0 · sourcepub 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,
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,
P: FnMut(&T) -> bool, type Item = &'a [T];
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:?}");
}
Run1.0.0 · sourcepub fn contains(&self, x: &T) -> bool where
T: PartialEq<T>,
pub fn contains(&self, x: &T) -> bool where
T: PartialEq<T>,
Returns true
if the slice contains an element with the given value.
This operation is O(n).
Note that if you have a sorted slice, binary_search
may be faster.
Examples
let v = [10, 40, 30];
assert!(v.contains(&30));
assert!(!v.contains(&50));
RunIf you do not have a &T
, but some other value that you can compare
with one (for example, String
implements PartialEq<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"));
Run1.0.0 · sourcepub fn starts_with(&self, needle: &[T]) -> bool where
T: PartialEq<T>,
pub fn starts_with(&self, needle: &[T]) -> bool where
T: PartialEq<T>,
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]));
RunAlways returns true
if needle
is an empty slice:
let v = &[10, 40, 30];
assert!(v.starts_with(&[]));
let v: &[u8] = &[];
assert!(v.starts_with(&[]));
Run1.0.0 · sourcepub fn ends_with(&self, needle: &[T]) -> bool where
T: PartialEq<T>,
pub fn ends_with(&self, needle: &[T]) -> bool where
T: PartialEq<T>,
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]));
RunAlways returns true
if needle
is an empty slice:
let v = &[10, 40, 30];
assert!(v.ends_with(&[]));
let v: &[u8] = &[];
assert!(v.ends_with(&[]));
Run1.51.0 · sourcepub fn strip_prefix<P>(&self, prefix: &P) -> Option<&[T]> where
P: SlicePattern<Item = T> + ?Sized,
T: PartialEq<T>,
pub fn strip_prefix<P>(&self, prefix: &P) -> Option<&[T]> where
P: SlicePattern<Item = T> + ?Sized,
T: PartialEq<T>,
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()));
Run1.51.0 · sourcepub fn strip_suffix<P>(&self, suffix: &P) -> Option<&[T]> where
P: SlicePattern<Item = T> + ?Sized,
T: PartialEq<T>,
pub fn strip_suffix<P>(&self, suffix: &P) -> Option<&[T]> where
P: SlicePattern<Item = T> + ?Sized,
T: PartialEq<T>,
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);
Run1.0.0 · sourcepub fn binary_search(&self, x: &T) -> Result<usize, usize> where
T: Ord,
pub fn binary_search(&self, x: &T) -> Result<usize, usize> where
T: Ord,
Binary searches this slice for a given element.
This behaves similary to contains
if this slice is sorted.
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. The index is chosen
deterministically, but is subject to change in future versions of Rust.
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, });
RunIf you want to insert an item to a sorted vector, while maintaining
sort order, consider using partition_point
:
let mut s = vec![0, 1, 1, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55];
let num = 42;
let idx = s.partition_point(|&x| x < num);
// The above is equivalent to `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]);
Run1.0.0 · sourcepub fn binary_search_by<'a, F>(&'a self, f: F) -> Result<usize, usize> where
F: FnMut(&'a T) -> Ordering,
pub fn binary_search_by<'a, F>(&'a self, f: F) -> Result<usize, usize> where
F: FnMut(&'a T) -> Ordering,
Binary searches this slice with a comparator function.
This behaves similarly to contains
if this slice is sorted.
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. The index is chosen
deterministically, but is subject to change in future versions of Rust.
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, });
Run1.10.0 · sourcepub 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,
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,
Binary searches this slice with a key extraction function.
This behaves similarly to contains
if this slice is sorted.
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. The index is chosen
deterministically, but is subject to change in future versions of Rust.
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, });
Run1.30.0 · sourcepub unsafe fn align_to<U>(&self) -> (&[T], &[U], &[T])
pub unsafe fn align_to<U>(&self) -> (&[T], &[U], &[T])
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);
}
Runsourcepub fn as_simd<const LANES: usize>(&self) -> (&[T], &[Simd<T, LANES>], &[T]) where
T: SimdElement,
Simd<T, LANES>: AsRef<[T; LANES]>,
LaneCount<LANES>: SupportedLaneCount,
pub fn as_simd<const LANES: usize>(&self) -> (&[T], &[Simd<T, LANES>], &[T]) where
T: SimdElement,
Simd<T, LANES>: AsRef<[T; LANES]>,
LaneCount<LANES>: SupportedLaneCount,
Split a slice into a prefix, a middle of aligned SIMD types, and a suffix.
This is a safe wrapper around slice::align_to
, so has the same weak
postconditions as that method. You’re only assured that
self.len() == prefix.len() + middle.len() * LANES + suffix.len()
.
Notably, all of the following are possible:
prefix.len() >= LANES
.middle.is_empty()
despiteself.len() >= 3 * LANES
.suffix.len() >= LANES
.
That said, this is a safe method, so if you’re only writing safe code, then this can at most cause incorrect logic, not unsoundness.
Panics
This will panic if the size of the SIMD type is different from
LANES
times that of the scalar.
At the time of writing, the trait restrictions on Simd<T, LANES>
keeps
that from ever happening, as only power-of-two numbers of lanes are
supported. It’s possible that, in the future, those restrictions might
be lifted in a way that would make it possible to see panics from this
method for something like LANES == 3
.
Examples
#![feature(portable_simd)]
let short = &[1, 2, 3];
let (prefix, middle, suffix) = short.as_simd::<4>();
assert_eq!(middle, []); // Not enough elements for anything in the middle
// They might be split in any possible way between prefix and suffix
let it = prefix.iter().chain(suffix).copied();
assert_eq!(it.collect::<Vec<_>>(), vec![1, 2, 3]);
fn basic_simd_sum(x: &[f32]) -> f32 {
use std::ops::Add;
use std::simd::f32x4;
let (prefix, middle, suffix) = x.as_simd();
let sums = f32x4::from_array([
prefix.iter().copied().sum(),
0.0,
0.0,
suffix.iter().copied().sum(),
]);
let sums = middle.iter().copied().fold(sums, f32x4::add);
sums.reduce_sum()
}
let numbers: Vec<f32> = (1..101).map(|x| x as _).collect();
assert_eq!(basic_simd_sum(&numbers[1..99]), 4949.0);
Runsourcepub fn is_sorted(&self) -> bool where
T: PartialOrd<T>,
pub fn is_sorted(&self) -> bool where
T: PartialOrd<T>,
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());
Runsourcepub fn is_sorted_by<F>(&self, compare: F) -> bool where
F: FnMut(&T, &T) -> Option<Ordering>,
pub fn is_sorted_by<F>(&self, compare: F) -> bool where
F: FnMut(&T, &T) -> Option<Ordering>,
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.
sourcepub fn is_sorted_by_key<F, K>(&self, f: F) -> bool where
F: FnMut(&T) -> K,
K: PartialOrd<K>,
pub fn is_sorted_by_key<F, K>(&self, f: F) -> bool where
F: FnMut(&T) -> K,
K: PartialOrd<K>,
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()));
Run1.52.0 · sourcepub fn partition_point<P>(&self, pred: P) -> usize where
P: FnMut(&T) -> bool,
pub fn partition_point<P>(&self, pred: P) -> usize where
P: FnMut(&T) -> bool,
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)));
RunIf 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.partition_point(|&x| x < num);
s.insert(idx, num);
assert_eq!(s, [0, 1, 1, 1, 1, 2, 3, 5, 8, 13, 21, 34, 42, 55]);
Run1.23.0 · sourcepub fn is_ascii(&self) -> bool
pub fn is_ascii(&self) -> bool
Checks if all bytes in this slice are within the ASCII range.
1.23.0 · sourcepub fn eq_ignore_ascii_case(&self, other: &[u8]) -> bool
pub fn eq_ignore_ascii_case(&self, other: &[u8]) -> bool
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.
1.60.0 · sourcepub fn escape_ascii(&self) -> EscapeAscii<'_>ⓘNotable traits for EscapeAscii<'a>impl<'a> Iterator for EscapeAscii<'a> type Item = u8;
pub fn escape_ascii(&self) -> EscapeAscii<'_>ⓘNotable traits for EscapeAscii<'a>impl<'a> Iterator for EscapeAscii<'a> type Item = u8;
sourcepub fn trim_ascii_start(&self) -> &[u8]ⓘNotable traits for &[u8]impl Read for &[u8]impl Write for &mut [u8]
pub fn trim_ascii_start(&self) -> &[u8]ⓘNotable traits for &[u8]impl Read for &[u8]impl Write for &mut [u8]
Returns a byte slice with leading ASCII whitespace bytes removed.
‘Whitespace’ refers to the definition used by
u8::is_ascii_whitespace
.
Examples
#![feature(byte_slice_trim_ascii)]
assert_eq!(b" \t hello world\n".trim_ascii_start(), b"hello world\n");
assert_eq!(b" ".trim_ascii_start(), b"");
assert_eq!(b"".trim_ascii_start(), b"");
Runsourcepub fn trim_ascii_end(&self) -> &[u8]ⓘNotable traits for &[u8]impl Read for &[u8]impl Write for &mut [u8]
pub fn trim_ascii_end(&self) -> &[u8]ⓘNotable traits for &[u8]impl Read for &[u8]impl Write for &mut [u8]
Returns a byte slice with trailing ASCII whitespace bytes removed.
‘Whitespace’ refers to the definition used by
u8::is_ascii_whitespace
.
Examples
#![feature(byte_slice_trim_ascii)]
assert_eq!(b"\r hello world\n ".trim_ascii_end(), b"\r hello world");
assert_eq!(b" ".trim_ascii_end(), b"");
assert_eq!(b"".trim_ascii_end(), b"");
Runsourcepub fn trim_ascii(&self) -> &[u8]ⓘNotable traits for &[u8]impl Read for &[u8]impl Write for &mut [u8]
pub fn trim_ascii(&self) -> &[u8]ⓘNotable traits for &[u8]impl Read for &[u8]impl Write for &mut [u8]
Returns a byte slice with leading and trailing ASCII whitespace bytes removed.
‘Whitespace’ refers to the definition used by
u8::is_ascii_whitespace
.
Examples
#![feature(byte_slice_trim_ascii)]
assert_eq!(b"\r hello world\n ".trim_ascii(), b"hello world");
assert_eq!(b" ".trim_ascii(), b"");
assert_eq!(b"".trim_ascii(), b"");
Runsourcepub fn flatten(&self) -> &[T]ⓘNotable traits for &[u8]impl Read for &[u8]impl Write for &mut [u8]
pub fn flatten(&self) -> &[T]ⓘNotable traits for &[u8]impl Read for &[u8]impl Write for &mut [u8]
Takes a &[[T; N]]
, and flattens it to a &[T]
.
Panics
This panics if the length of the resulting slice would overflow a usize
.
This is only possible when flattening a slice of arrays of zero-sized
types, and thus tends to be irrelevant in practice. If
size_of::<T>() > 0
, this will never panic.
Examples
#![feature(slice_flatten)]
assert_eq!([[1, 2, 3], [4, 5, 6]].flatten(), &[1, 2, 3, 4, 5, 6]);
assert_eq!(
[[1, 2, 3], [4, 5, 6]].flatten(),
[[1, 2], [3, 4], [5, 6]].flatten(),
);
let slice_of_empty_arrays: &[[i32; 0]] = &[[], [], [], [], []];
assert!(slice_of_empty_arrays.flatten().is_empty());
let empty_slice_of_arrays: &[[u32; 10]] = &[];
assert!(empty_slice_of_arrays.flatten().is_empty());
Run1.23.0 · sourcepub fn to_ascii_uppercase(&self) -> Vec<u8, Global>ⓘNotable traits for Vec<u8, A>impl<A: Allocator> Write for Vec<u8, A>
pub fn to_ascii_uppercase(&self) -> Vec<u8, Global>ⓘNotable traits for Vec<u8, A>impl<A: Allocator> Write for Vec<u8, A>
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
.
1.23.0 · sourcepub fn to_ascii_lowercase(&self) -> Vec<u8, Global>ⓘNotable traits for Vec<u8, A>impl<A: Allocator> Write for Vec<u8, A>
pub fn to_ascii_lowercase(&self) -> Vec<u8, Global>ⓘNotable traits for Vec<u8, A>impl<A: Allocator> Write for Vec<u8, A>
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
.
1.0.0 · sourcepub fn to_vec(&self) -> Vec<T, Global>ⓘNotable traits for Vec<u8, A>impl<A: Allocator> Write for Vec<u8, A>
where
T: Clone,
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,
sourcepub 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
A: Allocator,
T: Clone,
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
A: Allocator,
T: Clone,
1.40.0 · sourcepub 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,
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,
1.0.0 · sourcepub 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>,
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>,
1.3.0 · sourcepub 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>,
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>,
Trait Implementations
impl<'a> Copy for IoSlice<'a>
impl<'a> Send for IoSlice<'a>
impl<'a> Sync for IoSlice<'a>
Auto Trait Implementations
impl<'a> RefUnwindSafe for IoSlice<'a>
impl<'a> Unpin for IoSlice<'a>
impl<'a> UnwindSafe for IoSlice<'a>
Blanket Implementations
sourceimpl<T> BorrowMut<T> for T where
T: ?Sized,
impl<T> BorrowMut<T> for T where
T: ?Sized,
const: unstable · sourcefn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more