pub struct IntoIter<T, const N: usize> { /* private fields */ }
Expand description
A by-value array iterator.
Implementations§
source§impl<T, const N: usize> IntoIter<T, N>
impl<T, const N: usize> IntoIter<T, N>
sourcepub fn new(array: [T; N]) -> IntoIter<T, N> ⓘ
👎Deprecated since 1.59.0: use IntoIterator::into_iter
instead
pub fn new(array: [T; N]) -> IntoIter<T, N> ⓘ
IntoIterator::into_iter
insteadCreates a new iterator over the given array
.
const: unstable · sourcepub unsafe fn new_unchecked(
buffer: [MaybeUninit<T>; N],
initialized: Range<usize>
) -> IntoIter<T, N> ⓘ
🔬This is a nightly-only experimental API. (array_into_iter_constructors
#91583)
pub unsafe fn new_unchecked( buffer: [MaybeUninit<T>; N], initialized: Range<usize> ) -> IntoIter<T, N> ⓘ
array_into_iter_constructors
#91583)Creates an iterator over the elements in a partially-initialized buffer.
If you have a fully-initialized array, then use IntoIterator
.
But this is useful for returning partial results from unsafe code.
§Safety
- The
buffer[initialized]
elements must all be initialized. - The range must be canonical, with
initialized.start <= initialized.end
. - The range must be in-bounds for the buffer, with
initialized.end <= N
. (Like how indexing[0][100..100]
fails despite the range being empty.)
It’s sound to have more elements initialized than mentioned, though that will most likely result in them being leaked.
§Examples
#![feature(array_into_iter_constructors)]
#![feature(maybe_uninit_uninit_array_transpose)]
#![feature(maybe_uninit_uninit_array)]
use std::array::IntoIter;
use std::mem::MaybeUninit;
fn next_chunk<T: Copy, const N: usize>(
it: &mut impl Iterator<Item = T>,
) -> Result<[T; N], IntoIter<T, N>> {
let mut buffer = MaybeUninit::uninit_array();
let mut i = 0;
while i < N {
match it.next() {
Some(x) => {
buffer[i].write(x);
i += 1;
}
None => {
// SAFETY: We've initialized the first `i` items
unsafe {
return Err(IntoIter::new_unchecked(buffer, 0..i));
}
}
}
}
// SAFETY: We've initialized all N items
unsafe { Ok(buffer.transpose().assume_init()) }
}
let r: [_; 4] = next_chunk(&mut (10..16)).unwrap();
assert_eq!(r, [10, 11, 12, 13]);
let r: IntoIter<_, 40> = next_chunk(&mut (10..16)).unwrap_err();
assert_eq!(r.collect::<Vec<_>>(), vec![10, 11, 12, 13, 14, 15]);
Runconst: unstable · sourcepub fn empty() -> IntoIter<T, N> ⓘ
🔬This is a nightly-only experimental API. (array_into_iter_constructors
#91583)
pub fn empty() -> IntoIter<T, N> ⓘ
array_into_iter_constructors
#91583)Creates an iterator over T
which returns no elements.
If you just need an empty iterator, then use
iter::empty()
instead.
And if you need an empty array, use []
.
But this is useful when you need an array::IntoIter<T, N>
specifically.
§Examples
#![feature(array_into_iter_constructors)]
use std::array::IntoIter;
let empty = IntoIter::<i32, 3>::empty();
assert_eq!(empty.len(), 0);
assert_eq!(empty.as_slice(), &[]);
let empty = IntoIter::<std::convert::Infallible, 200>::empty();
assert_eq!(empty.len(), 0);
Run[1, 2].into_iter()
and [].into_iter()
have different types
#![feature(array_into_iter_constructors)]
use std::array::IntoIter;
pub fn get_bytes(b: bool) -> IntoIter<i8, 4> {
if b {
[1, 2, 3, 4].into_iter()
} else {
[].into_iter() // error[E0308]: mismatched types
}
}
But using this method you can get an empty iterator of appropriate size:
#![feature(array_into_iter_constructors)]
use std::array::IntoIter;
pub fn get_bytes(b: bool) -> IntoIter<i8, 4> {
if b {
[1, 2, 3, 4].into_iter()
} else {
IntoIter::empty()
}
}
assert_eq!(get_bytes(true).collect::<Vec<_>>(), vec![1, 2, 3, 4]);
assert_eq!(get_bytes(false).collect::<Vec<_>>(), vec![]);
Runsourcepub fn as_slice(&self) -> &[T]
pub fn as_slice(&self) -> &[T]
Returns an immutable slice of all elements that have not been yielded yet.
sourcepub fn as_mut_slice(&mut self) -> &mut [T]
pub fn as_mut_slice(&mut self) -> &mut [T]
Returns a mutable slice of all elements that have not been yielded yet.
Trait Implementations§
1.40.0 · source§impl<T, const N: usize> DoubleEndedIterator for IntoIter<T, N>
impl<T, const N: usize> DoubleEndedIterator for IntoIter<T, N>
source§fn next_back(&mut self) -> Option<<IntoIter<T, N> as Iterator>::Item>
fn next_back(&mut self) -> Option<<IntoIter<T, N> as Iterator>::Item>
source§fn rfold<Acc, Fold>(self, init: Acc, rfold: Fold) -> Acc
fn rfold<Acc, Fold>(self, init: Acc, rfold: Fold) -> Acc
source§fn advance_back_by(&mut self, n: usize) -> Result<(), NonZero<usize>>
fn advance_back_by(&mut self, n: usize) -> Result<(), NonZero<usize>>
iter_advance_by
#77404)n
elements. Read more1.37.0 · source§fn nth_back(&mut self, n: usize) -> Option<Self::Item>
fn nth_back(&mut self, n: usize) -> Option<Self::Item>
n
th element from the end of the iterator. Read more1.27.0 · source§fn try_rfold<B, F, R>(&mut self, init: B, f: F) -> R
fn try_rfold<B, F, R>(&mut self, init: B, f: F) -> R
Iterator::try_fold()
: it takes
elements starting from the back of the iterator. Read more1.40.0 · source§impl<T, const N: usize> ExactSizeIterator for IntoIter<T, N>
impl<T, const N: usize> ExactSizeIterator for IntoIter<T, N>
1.40.0 · source§impl<T, const N: usize> Iterator for IntoIter<T, N>
impl<T, const N: usize> Iterator for IntoIter<T, N>
source§fn next(&mut self) -> Option<<IntoIter<T, N> as Iterator>::Item>
fn next(&mut self) -> Option<<IntoIter<T, N> as Iterator>::Item>
source§fn size_hint(&self) -> (usize, Option<usize>)
fn size_hint(&self) -> (usize, Option<usize>)
source§fn fold<Acc, Fold>(self, init: Acc, fold: Fold) -> Acc
fn fold<Acc, Fold>(self, init: Acc, fold: Fold) -> Acc
source§fn count(self) -> usize
fn count(self) -> usize
source§fn last(self) -> Option<<IntoIter<T, N> as Iterator>::Item>
fn last(self) -> Option<<IntoIter<T, N> as Iterator>::Item>
source§fn advance_by(&mut self, n: usize) -> Result<(), NonZero<usize>>
fn advance_by(&mut self, n: usize) -> Result<(), NonZero<usize>>
iter_advance_by
#77404)n
elements. Read moresource§fn next_chunk<const N: usize>(
&mut self
) -> Result<[Self::Item; N], IntoIter<Self::Item, N>>where
Self: Sized,
fn next_chunk<const N: usize>(
&mut self
) -> Result<[Self::Item; N], IntoIter<Self::Item, N>>where
Self: Sized,
iter_next_chunk
#98326)N
values. Read more1.0.0 · source§fn nth(&mut self, n: usize) -> Option<Self::Item>
fn nth(&mut self, n: usize) -> Option<Self::Item>
n
th element of the iterator. Read more1.28.0 · source§fn step_by(self, step: usize) -> StepBy<Self> ⓘwhere
Self: Sized,
fn step_by(self, step: usize) -> StepBy<Self> ⓘwhere
Self: Sized,
1.0.0 · source§fn chain<U>(self, other: U) -> Chain<Self, <U as IntoIterator>::IntoIter> ⓘ
fn chain<U>(self, other: U) -> Chain<Self, <U as IntoIterator>::IntoIter> ⓘ
1.0.0 · source§fn zip<U>(self, other: U) -> Zip<Self, <U as IntoIterator>::IntoIter> ⓘwhere
Self: Sized,
U: IntoIterator,
fn zip<U>(self, other: U) -> Zip<Self, <U as IntoIterator>::IntoIter> ⓘwhere
Self: Sized,
U: IntoIterator,
source§fn intersperse_with<G>(self, separator: G) -> IntersperseWith<Self, G> ⓘ
fn intersperse_with<G>(self, separator: G) -> IntersperseWith<Self, G> ⓘ
iter_intersperse
#79524)separator
between adjacent items of the original iterator. Read more1.0.0 · source§fn map<B, F>(self, f: F) -> Map<Self, F> ⓘ
fn map<B, F>(self, f: F) -> Map<Self, F> ⓘ
1.0.0 · source§fn filter<P>(self, predicate: P) -> Filter<Self, P> ⓘ
fn filter<P>(self, predicate: P) -> Filter<Self, P> ⓘ
1.0.0 · source§fn filter_map<B, F>(self, f: F) -> FilterMap<Self, F> ⓘ
fn filter_map<B, F>(self, f: F) -> FilterMap<Self, F> ⓘ
1.0.0 · source§fn enumerate(self) -> Enumerate<Self> ⓘwhere
Self: Sized,
fn enumerate(self) -> Enumerate<Self> ⓘwhere
Self: Sized,
1.0.0 · source§fn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P> ⓘ
fn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P> ⓘ
1.0.0 · source§fn take_while<P>(self, predicate: P) -> TakeWhile<Self, P> ⓘ
fn take_while<P>(self, predicate: P) -> TakeWhile<Self, P> ⓘ
1.57.0 · source§fn map_while<B, P>(self, predicate: P) -> MapWhile<Self, P> ⓘ
fn map_while<B, P>(self, predicate: P) -> MapWhile<Self, P> ⓘ
1.0.0 · source§fn skip(self, n: usize) -> Skip<Self> ⓘwhere
Self: Sized,
fn skip(self, n: usize) -> Skip<Self> ⓘwhere
Self: Sized,
n
elements. Read more1.0.0 · source§fn take(self, n: usize) -> Take<Self> ⓘwhere
Self: Sized,
fn take(self, n: usize) -> Take<Self> ⓘwhere
Self: Sized,
n
elements, or fewer
if the underlying iterator ends sooner. Read more1.0.0 · source§fn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F> ⓘ
fn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F> ⓘ
source§fn map_windows<F, R, const N: usize>(self, f: F) -> MapWindows<Self, F, N> ⓘ
fn map_windows<F, R, const N: usize>(self, f: F) -> MapWindows<Self, F, N> ⓘ
iter_map_windows
#87155)f
for each contiguous window of size N
over
self
and returns an iterator over the outputs of f
. Like slice::windows()
,
the windows during mapping overlap as well. Read more1.0.0 · source§fn inspect<F>(self, f: F) -> Inspect<Self, F> ⓘ
fn inspect<F>(self, f: F) -> Inspect<Self, F> ⓘ
1.0.0 · source§fn by_ref(&mut self) -> &mut Selfwhere
Self: Sized,
fn by_ref(&mut self) -> &mut Selfwhere
Self: Sized,
source§fn collect_into<E>(self, collection: &mut E) -> &mut E
fn collect_into<E>(self, collection: &mut E) -> &mut E
iter_collect_into
#94780)1.0.0 · source§fn partition<B, F>(self, f: F) -> (B, B)
fn partition<B, F>(self, f: F) -> (B, B)
source§fn partition_in_place<'a, T, P>(self, predicate: P) -> usize
fn partition_in_place<'a, T, P>(self, predicate: P) -> usize
iter_partition_in_place
#62543)true
precede all those that return false
.
Returns the number of true
elements found. Read moresource§fn is_partitioned<P>(self, predicate: P) -> bool
fn is_partitioned<P>(self, predicate: P) -> bool
iter_is_partitioned
#62544)true
precede all those that return false
. Read more1.27.0 · source§fn try_fold<B, F, R>(&mut self, init: B, f: F) -> R
fn try_fold<B, F, R>(&mut self, init: B, f: F) -> R
1.27.0 · source§fn try_for_each<F, R>(&mut self, f: F) -> R
fn try_for_each<F, R>(&mut self, f: F) -> R
source§fn reduce<F>(self, f: F) -> Option<Self::Item>
fn reduce<F>(self, f: F) -> Option<Self::Item>
source§fn try_reduce<F, R>(
&mut self,
f: F
) -> <<R as Try>::Residual as Residual<Option<<R as Try>::Output>>>::TryType
fn try_reduce<F, R>( &mut self, f: F ) -> <<R as Try>::Residual as Residual<Option<<R as Try>::Output>>>::TryType
iterator_try_reduce
#87053)1.0.0 · source§fn all<F>(&mut self, f: F) -> bool
fn all<F>(&mut self, f: F) -> bool
1.0.0 · source§fn any<F>(&mut self, f: F) -> bool
fn any<F>(&mut self, f: F) -> bool
1.0.0 · source§fn find<P>(&mut self, predicate: P) -> Option<Self::Item>
fn find<P>(&mut self, predicate: P) -> Option<Self::Item>
1.30.0 · source§fn find_map<B, F>(&mut self, f: F) -> Option<B>
fn find_map<B, F>(&mut self, f: F) -> Option<B>
source§fn try_find<F, R>(
&mut self,
f: F
) -> <<R as Try>::Residual as Residual<Option<Self::Item>>>::TryType
fn try_find<F, R>( &mut self, f: F ) -> <<R as Try>::Residual as Residual<Option<Self::Item>>>::TryType
try_find
#63178)1.0.0 · source§fn position<P>(&mut self, predicate: P) -> Option<usize>
fn position<P>(&mut self, predicate: P) -> Option<usize>
1.0.0 · source§fn rposition<P>(&mut self, predicate: P) -> Option<usize>
fn rposition<P>(&mut self, predicate: P) -> Option<usize>
1.6.0 · source§fn max_by_key<B, F>(self, f: F) -> Option<Self::Item>
fn max_by_key<B, F>(self, f: F) -> Option<Self::Item>
1.15.0 · source§fn max_by<F>(self, compare: F) -> Option<Self::Item>
fn max_by<F>(self, compare: F) -> Option<Self::Item>
1.6.0 · source§fn min_by_key<B, F>(self, f: F) -> Option<Self::Item>
fn min_by_key<B, F>(self, f: F) -> Option<Self::Item>
1.15.0 · source§fn min_by<F>(self, compare: F) -> Option<Self::Item>
fn min_by<F>(self, compare: F) -> Option<Self::Item>
1.0.0 · source§fn rev(self) -> Rev<Self> ⓘwhere
Self: Sized + DoubleEndedIterator,
fn rev(self) -> Rev<Self> ⓘwhere
Self: Sized + DoubleEndedIterator,
1.0.0 · source§fn unzip<A, B, FromA, FromB>(self) -> (FromA, FromB)
fn unzip<A, B, FromA, FromB>(self) -> (FromA, FromB)
1.36.0 · source§fn copied<'a, T>(self) -> Copied<Self> ⓘ
fn copied<'a, T>(self) -> Copied<Self> ⓘ
source§fn array_chunks<const N: usize>(self) -> ArrayChunks<Self, N> ⓘwhere
Self: Sized,
fn array_chunks<const N: usize>(self) -> ArrayChunks<Self, N> ⓘwhere
Self: Sized,
iter_array_chunks
#100450)N
elements of the iterator at a time. Read more1.11.0 · source§fn product<P>(self) -> P
fn product<P>(self) -> P
source§fn cmp_by<I, F>(self, other: I, cmp: F) -> Ordering
fn cmp_by<I, F>(self, other: I, cmp: F) -> Ordering
iter_order_by
#64295)Iterator
with those
of another with respect to the specified comparison function. Read more1.5.0 · source§fn partial_cmp<I>(self, other: I) -> Option<Ordering>
fn partial_cmp<I>(self, other: I) -> Option<Ordering>
PartialOrd
elements of
this Iterator
with those of another. The comparison works like short-circuit
evaluation, returning a result without comparing the remaining elements.
As soon as an order can be determined, the evaluation stops and a result is returned. Read moresource§fn partial_cmp_by<I, F>(self, other: I, partial_cmp: F) -> Option<Ordering>where
Self: Sized,
I: IntoIterator,
F: FnMut(Self::Item, <I as IntoIterator>::Item) -> Option<Ordering>,
fn partial_cmp_by<I, F>(self, other: I, partial_cmp: F) -> Option<Ordering>where
Self: Sized,
I: IntoIterator,
F: FnMut(Self::Item, <I as IntoIterator>::Item) -> Option<Ordering>,
iter_order_by
#64295)Iterator
with those
of another with respect to the specified comparison function. Read moresource§fn eq_by<I, F>(self, other: I, eq: F) -> bool
fn eq_by<I, F>(self, other: I, eq: F) -> bool
iter_order_by
#64295)1.5.0 · source§fn lt<I>(self, other: I) -> bool
fn lt<I>(self, other: I) -> bool
Iterator
are lexicographically
less than those of another. Read more1.5.0 · source§fn le<I>(self, other: I) -> bool
fn le<I>(self, other: I) -> bool
Iterator
are lexicographically
less or equal to those of another. Read more1.5.0 · source§fn gt<I>(self, other: I) -> bool
fn gt<I>(self, other: I) -> bool
Iterator
are lexicographically
greater than those of another. Read more1.5.0 · source§fn ge<I>(self, other: I) -> bool
fn ge<I>(self, other: I) -> bool
Iterator
are lexicographically
greater than or equal to those of another. Read moresource§fn is_sorted_by<F>(self, compare: F) -> bool
fn is_sorted_by<F>(self, compare: F) -> bool
is_sorted
#53485)