Struct iovec::IoVec
[−]
[src]
pub struct IoVec { /* fields omitted */ }
A specialized byte slice type for performing vectored I/O operations.
On all systems, the types needed to perform vectored I/O systems have the
same size as Rust's [slice]. However, the layout is not necessarily the
same. IoVec
provides a portable compatibility layer.
The IoVec
behaves like like a Rust [slice], providing the same functions.
It also provides conversion functions to and from the OS specific vectored
types.
Examples
use iovec::IoVec; let mut data = vec![]; data.extend_from_slice(b"hello"); let iovec: &IoVec = data.as_slice().into(); assert_eq!(&iovec[..], &b"hello"[..]);
Panics
Attempting to convert a zero-length slice or a slice longer than
MAX_LENGTH
to an IoVec
will result in a panic.
Methods
impl IoVec
[src]
fn from_bytes(slice: &[u8]) -> Option<&IoVec>
[src]
fn from_bytes_mut(slice: &mut [u8]) -> Option<&mut IoVec>
[src]
Methods from Deref<Target = [u8]>
fn len(&self) -> usize
1.0.0[src]
fn is_empty(&self) -> bool
1.0.0[src]
fn first(&self) -> Option<&T>
1.0.0[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());
fn first_mut(&mut self) -> Option<&mut T>
1.0.0[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]);
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]); }
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]);
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]); }
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]);
fn last(&self) -> Option<&T>
1.0.0[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());
fn last_mut(&mut self) -> Option<&mut T>
1.0.0[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]);
fn get<I>(&self, index: I) -> Option<&<I as SliceIndex<[T]>>::Output> where
I: SliceIndex<[T]>,
1.0.0[src]
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));
fn get_mut<I>(
&mut self,
index: I
) -> Option<&mut <I as SliceIndex<[T]>>::Output> where
I: SliceIndex<[T]>,
1.0.0[src]
&mut self,
index: I
) -> Option<&mut <I as SliceIndex<[T]>>::Output> where
I: SliceIndex<[T]>,
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]);
unsafe fn get_unchecked<I>(&self, index: I) -> &<I as SliceIndex<[T]>>::Output where
I: SliceIndex<[T]>,
1.0.0[src]
I: SliceIndex<[T]>,
Returns a reference to an element or subslice, without doing bounds checking.
This is generally not recommended, use with caution! For a safe
alternative see get
.
Examples
let x = &[1, 2, 4]; unsafe { assert_eq!(x.get_unchecked(1), &2); }
unsafe fn get_unchecked_mut<I>(
&mut self,
index: I
) -> &mut <I as SliceIndex<[T]>>::Output where
I: SliceIndex<[T]>,
1.0.0[src]
&mut self,
index: I
) -> &mut <I as SliceIndex<[T]>>::Output where
I: SliceIndex<[T]>,
Returns a mutable reference to an element or subslice, without doing bounds checking.
This is generally not recommended, use with caution! For a safe
alternative see get_mut
.
Examples
let x = &mut [1, 2, 4]; unsafe { let elem = x.get_unchecked_mut(1); *elem = 13; } assert_eq!(x, &[1, 13, 4]);
fn as_ptr(&self) -> *const T
1.0.0[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.
Modifying the container referenced by this slice may cause its buffer to be reallocated, which would also make any pointers to it invalid.
Examples
let x = &[1, 2, 4]; let x_ptr = x.as_ptr(); unsafe { for i in 0..x.len() { assert_eq!(x.get_unchecked(i), &*x_ptr.offset(i as isize)); } }
fn as_mut_ptr(&mut self) -> *mut T
1.0.0[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.offset(i as isize) += 2; } } assert_eq!(x, &[3, 4, 6]);
fn swap(&mut self, a: usize, b: usize)
1.0.0[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"]);
fn reverse(&mut self)
1.0.0[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]);
fn iter(&self) -> Iter<T>
1.0.0[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);
fn iter_mut(&mut self) -> IterMut<T>
1.0.0[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]);
fn windows(&self, size: usize) -> Windows<T>
1.0.0[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());
If the slice is shorter than size
:
let slice = ['f', 'o', 'o']; let mut iter = slice.windows(4); assert!(iter.next().is_none());
fn chunks(&self, size: usize) -> Chunks<T>
1.0.0[src]
Returns an iterator over size
elements of the slice at a
time. The chunks are slices and do not overlap. If size
does
not divide the length of the slice, then the last chunk will
not have length size
.
Panics
Panics if 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());
fn chunks_mut(&mut self, chunk_size: usize) -> ChunksMut<T>
1.0.0[src]
Returns an iterator over chunk_size
elements of the slice at a time.
The chunks are mutable slices, and do not overlap. If chunk_size
does
not divide the length of the slice, then the last chunk will not
have length chunk_size
.
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]);
fn split_at(&self, mid: usize) -> (&[T], &[T])
1.0.0[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 = [10, 40, 30, 20, 50]; let (v1, v2) = v.split_at(2); assert_eq!([10, 40], v1); assert_eq!([30, 20, 50], v2);
fn split_at_mut(&mut self, mid: usize) -> (&mut [T], &mut [T])
1.0.0[src]
Divides one &mut
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, 2, 3, 4, 5, 6]; // scoped to restrict the lifetime of the borrows { let (left, right) = v.split_at_mut(0); assert!(left == []); assert!(right == [1, 2, 3, 4, 5, 6]); } { let (left, right) = v.split_at_mut(2); assert!(left == [1, 2]); assert!(right == [3, 4, 5, 6]); } { let (left, right) = v.split_at_mut(6); assert!(left == [1, 2, 3, 4, 5, 6]); assert!(right == []); }
fn split<F>(&self, pred: F) -> Split<T, F> where
F: FnMut(&T) -> bool,
1.0.0[src]
F: FnMut(&T) -> bool,
Returns an iterator over subslices separated by elements that match
pred
. The matched element is not contained in the subslices.
Examples
let slice = [10, 40, 33, 20]; let mut iter = slice.split(|num| num % 3 == 0); assert_eq!(iter.next().unwrap(), &[10, 40]); assert_eq!(iter.next().unwrap(), &[20]); assert!(iter.next().is_none());
If the first element is matched, an empty slice will be the first item returned by the iterator. Similarly, if the last element in the slice is matched, an empty slice will be the last item returned by the iterator:
let slice = [10, 40, 33]; let mut iter = slice.split(|num| num % 3 == 0); assert_eq!(iter.next().unwrap(), &[10, 40]); assert_eq!(iter.next().unwrap(), &[]); assert!(iter.next().is_none());
If two matched elements are directly adjacent, an empty slice will be present between them:
let slice = [10, 6, 33, 20]; let mut iter = slice.split(|num| num % 3 == 0); assert_eq!(iter.next().unwrap(), &[10]); assert_eq!(iter.next().unwrap(), &[]); assert_eq!(iter.next().unwrap(), &[20]); assert!(iter.next().is_none());
fn split_mut<F>(&mut self, pred: F) -> SplitMut<T, F> where
F: FnMut(&T) -> bool,
1.0.0[src]
F: FnMut(&T) -> bool,
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]);
fn rsplit<F>(&self, pred: F) -> RSplit<T, F> where
F: FnMut(&T) -> bool,
[src]
F: FnMut(&T) -> bool,
slice_rsplit
)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
#![feature(slice_rsplit)] let slice = [11, 22, 33, 0, 44, 55]; let mut iter = slice.rsplit(|num| *num == 0); assert_eq!(iter.next().unwrap(), &[44, 55]); assert_eq!(iter.next().unwrap(), &[11, 22, 33]); assert_eq!(iter.next(), None);
As with split()
, if the first or last element is matched, an empty
slice will be the first (or last) item returned by the iterator.
#![feature(slice_rsplit)] 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);
fn rsplit_mut<F>(&mut self, pred: F) -> RSplitMut<T, F> where
F: FnMut(&T) -> bool,
[src]
F: FnMut(&T) -> bool,
slice_rsplit
)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
#![feature(slice_rsplit)] 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]);
fn splitn<F>(&self, n: usize, pred: F) -> SplitN<T, F> where
F: FnMut(&T) -> bool,
1.0.0[src]
F: FnMut(&T) -> bool,
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); }
fn splitn_mut<F>(&mut self, n: usize, pred: F) -> SplitNMut<T, F> where
F: FnMut(&T) -> bool,
1.0.0[src]
F: FnMut(&T) -> bool,
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]);
fn rsplitn<F>(&self, n: usize, pred: F) -> RSplitN<T, F> where
F: FnMut(&T) -> bool,
1.0.0[src]
F: FnMut(&T) -> bool,
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); }
fn rsplitn_mut<F>(&mut self, n: usize, pred: F) -> RSplitNMut<T, F> where
F: FnMut(&T) -> bool,
1.0.0[src]
F: FnMut(&T) -> bool,
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]);
fn contains(&self, x: &T) -> bool where
T: PartialEq<T>,
1.0.0[src]
T: PartialEq<T>,
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));
fn starts_with(&self, needle: &[T]) -> bool where
T: PartialEq<T>,
1.0.0[src]
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]));
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(&[]));
fn ends_with(&self, needle: &[T]) -> bool where
T: PartialEq<T>,
1.0.0[src]
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]));
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(&[]));
fn binary_search(&self, x: &T) -> Result<usize, usize> where
T: Ord,
1.0.0[src]
T: Ord,
Binary searches this sorted slice for a given element.
If the value is found then Ok
is returned, containing the
index of the matching element; if the value is not found then
Err
is returned, containing the index where a matching
element could be inserted while maintaining sorted order.
Examples
Looks up a series of four elements. The first is found, with a
uniquely determined position; the second and third are not
found; the fourth could match any position in [1, 4]
.
let s = [0, 1, 1, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55]; assert_eq!(s.binary_search(&13), Ok(9)); assert_eq!(s.binary_search(&4), Err(7)); assert_eq!(s.binary_search(&100), Err(13)); let r = s.binary_search(&1); assert!(match r { Ok(1...4) => true, _ => false, });
fn binary_search_by<'a, F>(&'a self, f: F) -> Result<usize, usize> where
F: FnMut(&'a T) -> Ordering,
1.0.0[src]
F: FnMut(&'a T) -> Ordering,
Binary searches this sorted slice with a comparator function.
The comparator function should implement an order consistent
with the sort order of the underlying slice, returning an
order code that indicates whether its argument is Less
,
Equal
or Greater
the desired target.
If a matching value is found then returns Ok
, containing
the index for the matched element; if no match is found then
Err
is returned, containing the index where a matching
element could be inserted while maintaining sorted order.
Examples
Looks up a series of four elements. The first is found, with a
uniquely determined position; the second and third are not
found; the fourth could match any position in [1, 4]
.
let s = [0, 1, 1, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55]; let seek = 13; assert_eq!(s.binary_search_by(|probe| probe.cmp(&seek)), Ok(9)); let seek = 4; assert_eq!(s.binary_search_by(|probe| probe.cmp(&seek)), Err(7)); let seek = 100; assert_eq!(s.binary_search_by(|probe| probe.cmp(&seek)), Err(13)); let seek = 1; let r = s.binary_search_by(|probe| probe.cmp(&seek)); assert!(match r { Ok(1...4) => true, _ => false, });
fn binary_search_by_key<'a, B, F>(&'a self, b: &B, f: F) -> Result<usize, usize> where
B: Ord,
F: FnMut(&'a T) -> B,
1.10.0[src]
B: Ord,
F: FnMut(&'a T) -> B,
Binary searches this sorted slice with a key extraction function.
Assumes that the slice is sorted by the key, for instance with
sort_by_key
using the same key extraction function.
If a matching value is found then returns Ok
, containing the
index for the matched element; if no match is found then Err
is returned, containing the index where a matching element could
be inserted while maintaining sorted order.
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, });
fn sort(&mut self) where
T: Ord,
1.0.0[src]
T: Ord,
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]);
fn sort_by<F>(&mut self, compare: F) where
F: FnMut(&T, &T) -> Ordering,
1.0.0[src]
F: FnMut(&T, &T) -> Ordering,
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.
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]);
fn sort_by_key<B, F>(&mut self, f: F) where
B: Ord,
F: FnMut(&T) -> B,
1.7.0[src]
B: Ord,
F: FnMut(&T) -> B,
Sorts the slice with a key extraction function.
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_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]);
fn sort_unstable(&mut self) where
T: Ord,
1.20.0[src]
T: Ord,
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]);
fn sort_unstable_by<F>(&mut self, compare: F) where
F: FnMut(&T, &T) -> Ordering,
1.20.0[src]
F: FnMut(&T, &T) -> Ordering,
Sorts the slice with a comparator function, but may not preserve the order of equal elements.
This sort is unstable (i.e. may reorder equal elements), in-place (i.e. does not allocate),
and O(n log n)
worst-case.
Current implementation
The current algorithm is based on pattern-defeating quicksort 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]);
fn sort_unstable_by_key<B, F>(&mut self, f: F) where
B: Ord,
F: FnMut(&T) -> B,
1.20.0[src]
B: Ord,
F: FnMut(&T) -> B,
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(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 = [-5i32, 4, 1, -3, 2]; v.sort_unstable_by_key(|k| k.abs()); assert!(v == [1, 2, -3, 4, -5]);
fn rotate(&mut self, mid: usize)
[src]
slice_rotate
)Permutes the slice in-place such that self[mid..]
moves to the
beginning of the slice while self[..mid]
moves to the end of the
slice. Equivalently, rotates the slice mid
places to the left
or k = self.len() - mid
places to the right.
This is a "k-rotation", a permutation in which item i
moves to
position i + k
, modulo the length of the slice. See Elements
of Programming §10.4.
Rotation by mid
and rotation by k
are inverse operations.
Panics
This function will panic if mid
is greater than the length of the
slice. (Note that mid == self.len()
does not panic; it's a nop
rotation with k == 0
, the inverse of a rotation with mid == 0
.)
Complexity
Takes linear (in self.len()
) time.
Examples
#![feature(slice_rotate)] let mut a = [1, 2, 3, 4, 5, 6, 7]; let mid = 2; a.rotate(mid); assert_eq!(&a, &[3, 4, 5, 6, 7, 1, 2]); let k = a.len() - mid; a.rotate(k); assert_eq!(&a, &[1, 2, 3, 4, 5, 6, 7]); use std::ops::Range; fn slide<T>(slice: &mut [T], range: Range<usize>, to: usize) { if to < range.start { slice[to..range.end].rotate(range.start-to); } else if to > range.end { slice[range.start..to].rotate(range.end-range.start); } } let mut v: Vec<_> = (0..10).collect(); slide(&mut v, 1..4, 7); assert_eq!(&v, &[0, 4, 5, 6, 1, 2, 3, 7, 8, 9]); slide(&mut v, 6..8, 1); assert_eq!(&v, &[0, 3, 7, 4, 5, 6, 1, 2, 8, 9]);
fn clone_from_slice(&mut self, src: &[T]) where
T: Clone,
1.7.0[src]
T: Clone,
Copies the elements from src
into self
.
The length of src
must be the same as self
.
If src
implements Copy
, it can be more performant to use
copy_from_slice
.
Panics
This function will panic if the two slices have different lengths.
Examples
let mut dst = [0, 0, 0]; let src = [1, 2, 3]; dst.clone_from_slice(&src); assert!(dst == [1, 2, 3]);
fn copy_from_slice(&mut self, src: &[T]) where
T: Copy,
1.9.0[src]
T: Copy,
Copies all elements from src
into self
, using a memcpy.
The length of src
must be the same as self
.
If src
does not implement Copy
, use clone_from_slice
.
Panics
This function will panic if the two slices have different lengths.
Examples
let mut dst = [0, 0, 0]; let src = [1, 2, 3]; dst.copy_from_slice(&src); assert_eq!(src, dst);
fn swap_with_slice(&mut self, src: &mut [T])
[src]
swap_with_slice
)Swaps all elements in self
with those in src
.
The length of src
must be the same as self
.
Panics
This function will panic if the two slices have different lengths.
Example
#![feature(swap_with_slice)] let mut src = [1, 2, 3]; let mut dst = [7, 8, 9]; src.swap_with_slice(&mut dst); assert_eq!(src, [7, 8, 9]); assert_eq!(dst, [1, 2, 3]);
fn to_vec(&self) -> Vec<T> where
T: Clone,
1.0.0[src]
T: Clone,
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.
Trait Implementations
impl Deref for IoVec
[src]
type Target = [u8]
The resulting type after dereferencing.
fn deref(&self) -> &[u8]
[src]
Dereferences the value.