1.0.0[−]Primitive Type array
A fixed-size array, denoted [T; N], for the element type, T, and the
non-negative compile-time constant size, N.
There are two syntactic forms for creating an array:
- A list with each element, i.e.,
[x, y, z]. - A repeat expression
[x; N], which produces an array withNcopies ofx. The type ofxmust beCopy.
Arrays of any size implement the following traits if the element type allows it:
DebugIntoIterator(implemented for&[T; N]and&mut [T; N])PartialEq,PartialOrd,Eq,OrdHashAsRef,AsMutBorrow,BorrowMut
Arrays of sizes from 0 to 32 (inclusive) implement Default trait
if the element type allows it. As a stopgap, trait implementations are
statically generated up to size 32.
Arrays of any size are Copy if the element type is Copy
and Clone if the element type is Clone. This works
because Copy and Clone traits are specially known
to the compiler.
Arrays coerce to slices ([T]), so a slice method may be called on
an array. Indeed, this provides most of the API for working with arrays.
Slices have a dynamic size and do not coerce to arrays.
You can move elements out of an array with a slice pattern. If you want
one element, see mem::replace.
Examples
let mut array: [i32; 3] = [0; 3]; array[1] = 1; array[2] = 2; assert_eq!([1, 2], &array[1..]); // This loop prints: 0 1 2 for x in &array { print!("{} ", x); }Run
An array itself is not iterable:
let array: [i32; 3] = [0; 3]; for x in array { } // error: the trait bound `[i32; 3]: std::iter::Iterator` is not satisfiedRun
The solution is to coerce the array to a slice by calling a slice method:
for x in array.iter() { }Run
You can also use the array reference's IntoIterator implementation:
for x in &array { }Run
You can use a slice pattern to move elements out of an array:
fn move_away(_: String) { /* Do interesting things. */ } let [john, roa] = ["John".to_string(), "Roa".to_string()]; move_away(john); move_away(roa);Run
Implementations
impl<T, const N: usize> [T; N][src]
pub fn map<F, U>(self, f: F) -> [U; N] where
F: FnMut(T) -> U, [src]
F: FnMut(T) -> U,
Returns an array of the same size as self, with function f applied to each element
in order.
Examples
#![feature(array_map)] let x = [1, 2, 3]; let y = x.map(|v| v + 1); assert_eq!(y, [2, 3, 4]); let x = [1, 2, 3]; let mut temp = 0; let y = x.map(|v| { temp += 1; v * temp }); assert_eq!(y, [1, 4, 9]); let x = ["Ferris", "Bueller's", "Day", "Off"]; let y = x.map(|v| v.len()); assert_eq!(y, [6, 9, 3, 3]);Run
pub fn as_slice(&self) -> &[T]ⓘ[src]
Returns a slice containing the entire array. Equivalent to &s[..].
pub fn as_mut_slice(&mut self) -> &mut [T]ⓘ[src]
Returns a mutable slice containing the entire array. Equivalent to
&mut s[..].
Trait Implementations
impl<T, const N: usize> AsMut<[T]> for [T; N][src]
impl<T, const N: usize> AsRef<[T]> for [T; N][src]
impl<T, const N: usize> Borrow<[T]> for [T; N]1.4.0[src]
impl<T, const N: usize> BorrowMut<[T]> for [T; N]1.4.0[src]
fn borrow_mut(&mut self) -> &mut [T]ⓘ[src]
impl<T, const N: usize> Debug for [T; N] where
T: Debug, [src]
T: Debug,
impl<T> Default for [T; 31] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 8] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 4] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 9] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 11] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 15] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 30] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 21] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 14] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 28] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 29] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 0]1.4.0[src]
impl<T> Default for [T; 32] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 27] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 22] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 10] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 3] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 19] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 13] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 2] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 24] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 25] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 5] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 7] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 23] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 17] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 1] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 12] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 20] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 26] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 18] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 16] where
T: Default, 1.4.0[src]
T: Default,
impl<T> Default for [T; 6] where
T: Default, 1.4.0[src]
T: Default,
impl<T, const N: usize> Eq for [T; N] where
T: Eq, [src]
T: Eq,
impl<T, const N: usize> Hash for [T; N] where
T: Hash, [src]
T: Hash,
fn hash<H>(&self, state: &mut H) where
H: Hasher, [src]
H: Hasher,
fn hash_slice<H>(data: &[Self], state: &mut H) where
H: Hasher, 1.3.0[src]
H: Hasher,
impl<'a, T, const N: usize> IntoIterator for &'a mut [T; N][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?
fn into_iter(self) -> IterMut<'a, T>ⓘ[src]
impl<'a, T, const N: usize> IntoIterator for &'a [T; N][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?
fn into_iter(self) -> Iter<'a, T>ⓘ[src]
impl<T, const N: usize> Ord for [T; N] where
T: Ord, [src]
T: Ord,
Implements comparison of arrays lexicographically.
fn cmp(&self, other: &[T; N]) -> Ordering[src]
#[must_use]fn max(self, other: Self) -> Self1.21.0[src]
#[must_use]fn min(self, other: Self) -> Self1.21.0[src]
#[must_use]fn clamp(self, min: Self, max: Self) -> Self[src]
impl<'b, A, B, const N: usize> PartialEq<&'b [B]> for [A; N] where
A: PartialEq<B>, [src]
A: PartialEq<B>,
impl<'b, A, B, const N: usize> PartialEq<&'b mut [B]> for [A; N] where
A: PartialEq<B>, [src]
A: PartialEq<B>,
fn eq(&self, other: &&'b mut [B]) -> bool[src]
fn ne(&self, other: &&'b mut [B]) -> bool[src]
impl<A, B, const N: usize> PartialEq<[B; N]> for [A; N] where
A: PartialEq<B>, [src]
A: PartialEq<B>,
impl<A, B, const N: usize> PartialEq<[B]> for [A; N] where
A: PartialEq<B>, [src]
A: PartialEq<B>,
impl<T, const N: usize> PartialOrd<[T; N]> for [T; N] where
T: PartialOrd<T>, [src]
T: PartialOrd<T>,
fn partial_cmp(&self, other: &[T; N]) -> Option<Ordering>[src]
fn lt(&self, other: &[T; N]) -> bool[src]
fn le(&self, other: &[T; N]) -> bool[src]
fn ge(&self, other: &[T; N]) -> bool[src]
fn gt(&self, other: &[T; N]) -> bool[src]
impl<'_, T, const N: usize> TryFrom<&'_ [T]> for [T; N] where
T: Copy, 1.34.0[src]
T: Copy,
type Error = TryFromSliceError
The type returned in the event of a conversion error.
fn try_from(slice: &[T]) -> Result<[T; N], TryFromSliceError>[src]
impl<'a, T, const N: usize> TryFrom<&'a [T]> for &'a [T; N]1.34.0[src]
type Error = TryFromSliceError
The type returned in the event of a conversion error.
fn try_from(slice: &[T]) -> Result<&[T; N], TryFromSliceError>[src]
impl<'a, T, const N: usize> TryFrom<&'a mut [T]> for &'a mut [T; N]1.34.0[src]
type Error = TryFromSliceError
The type returned in the event of a conversion error.
fn try_from(slice: &mut [T]) -> Result<&mut [T; N], TryFromSliceError>[src]
impl<T, const N: usize> TryFrom<Vec<T>> for [T; N]1.48.0[src]
type Error = Vec<T>
The type returned in the event of a conversion error.
fn try_from(vec: Vec<T>) -> Result<[T; N], Vec<T>>[src]
Gets the entire contents of the Vec<T> as an array,
if its size exactly matches that of the requested array.
Examples
use std::convert::TryInto; assert_eq!(vec![1, 2, 3].try_into(), Ok([1, 2, 3])); assert_eq!(<Vec<i32>>::new().try_into(), Ok([]));Run
If the length doesn't match, the input comes back in Err:
use std::convert::TryInto; let r: Result<[i32; 4], _> = (0..10).collect::<Vec<_>>().try_into(); assert_eq!(r, Err(vec![0, 1, 2, 3, 4, 5, 6, 7, 8, 9]));Run
If you're fine with just getting a prefix of the Vec<T>,
you can call .truncate(N) first.
use std::convert::TryInto; let mut v = String::from("hello world").into_bytes(); v.sort(); v.truncate(2); let [a, b]: [_; 2] = v.try_into().unwrap(); assert_eq!(a, b' '); assert_eq!(b, b'd');Run
Auto Trait Implementations
impl<T, const N: usize> RefUnwindSafe for [T; N] where
T: RefUnwindSafe,
T: RefUnwindSafe,
impl<T, const N: usize> Send for [T; N] where
T: Send,
T: Send,
impl<T, const N: usize> Sync for [T; N] where
T: Sync,
T: Sync,
impl<T, const N: usize> Unpin for [T; N] where
T: Unpin,
T: Unpin,
impl<T, const N: usize> UnwindSafe for [T; N] where
T: UnwindSafe,
T: UnwindSafe,
Blanket Implementations
impl<T> Any for T where
T: 'static + ?Sized, [src]
T: 'static + ?Sized,
impl<T> Borrow<T> for T where
T: ?Sized, [src]
T: ?Sized,
fn borrow(&self) -> &TⓘNotable traits for &'_ mut F
impl<'_, F> Future for &'_ mut F where
F: Unpin + Future + ?Sized, type Output = <F as Future>::Output;impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized, type Item = <I as Iterator>::Item;impl<R: Read + ?Sized, '_> Read for &'_ mut Rimpl<W: Write + ?Sized, '_> Write for &'_ mut W[src]
Notable traits for &'_ mut F
impl<'_, F> Future for &'_ mut F where
F: Unpin + Future + ?Sized, type Output = <F as Future>::Output;impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized, type Item = <I as Iterator>::Item;impl<R: Read + ?Sized, '_> Read for &'_ mut Rimpl<W: Write + ?Sized, '_> Write for &'_ mut Wimpl<T> BorrowMut<T> for T where
T: ?Sized, [src]
T: ?Sized,
fn borrow_mut(&mut self) -> &mut TⓘNotable traits for &'_ mut F
impl<'_, F> Future for &'_ mut F where
F: Unpin + Future + ?Sized, type Output = <F as Future>::Output;impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized, type Item = <I as Iterator>::Item;impl<R: Read + ?Sized, '_> Read for &'_ mut Rimpl<W: Write + ?Sized, '_> Write for &'_ mut W[src]
Notable traits for &'_ mut F
impl<'_, F> Future for &'_ mut F where
F: Unpin + Future + ?Sized, type Output = <F as Future>::Output;impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized, type Item = <I as Iterator>::Item;impl<R: Read + ?Sized, '_> Read for &'_ mut Rimpl<W: Write + ?Sized, '_> Write for &'_ mut Wimpl<T, A> FixedSizeArray<T> for A where
A: Unsize<[T]>, [src]
A: Unsize<[T]>,
impl<T> From<T> for T[src]
impl<T, U> Into<U> for T where
U: From<T>, [src]
U: From<T>,
impl<T> ToOwned for T where
T: Clone, [src]
T: Clone,
type Owned = T
The resulting type after obtaining ownership.
fn to_owned(&self) -> T[src]
fn clone_into(&self, target: &mut T)[src]
impl<T, U> TryFrom<U> for T where
U: Into<T>, [src]
U: Into<T>,
type Error = Infallible
The type returned in the event of a conversion error.
fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>[src]
impl<T, U> TryInto<U> for T where
U: TryFrom<T>, [src]
U: TryFrom<T>,