Trait otter_base::imports::iter::IntoIterator
1.0.0 · source · [−]pub trait IntoIterator {
type Item;
type IntoIter: Iterator
where
<Self::IntoIter as Iterator>::Item == Self::Item;
fn into_iter(self) -> Self::IntoIter;
}
Expand description
Conversion into an Iterator
.
By implementing IntoIterator
for a type, you define how it will be
converted to an iterator. This is common for types which describe a
collection of some kind.
One benefit of implementing IntoIterator
is that your type will work
with Rust’s for
loop syntax.
See also: FromIterator
.
Examples
Basic usage:
let v = [1, 2, 3];
let mut iter = v.into_iter();
assert_eq!(Some(1), iter.next());
assert_eq!(Some(2), iter.next());
assert_eq!(Some(3), iter.next());
assert_eq!(None, iter.next());
Implementing IntoIterator
for your type:
// A sample collection, that's just a wrapper over Vec<T>
#[derive(Debug)]
struct MyCollection(Vec<i32>);
// Let's give it some methods so we can create one and add things
// to it.
impl MyCollection {
fn new() -> MyCollection {
MyCollection(Vec::new())
}
fn add(&mut self, elem: i32) {
self.0.push(elem);
}
}
// and we'll implement IntoIterator
impl IntoIterator for MyCollection {
type Item = i32;
type IntoIter = std::vec::IntoIter<Self::Item>;
fn into_iter(self) -> Self::IntoIter {
self.0.into_iter()
}
}
// Now we can make a new collection...
let mut c = MyCollection::new();
// ... add some stuff to it ...
c.add(0);
c.add(1);
c.add(2);
// ... and then turn it into an Iterator:
for (i, n) in c.into_iter().enumerate() {
assert_eq!(i as i32, n);
}
It is common to use IntoIterator
as a trait bound. This allows
the input collection type to change, so long as it is still an
iterator. Additional bounds can be specified by restricting on
Item
:
fn collect_as_strings<T>(collection: T) -> Vec<String>
where
T: IntoIterator,
T::Item: std::fmt::Debug,
{
collection
.into_iter()
.map(|item| format!("{item:?}"))
.collect()
}
Required Associated Types
Required Methods
Creates an iterator from a value.
See the module-level documentation for more.
Examples
Basic usage:
let v = [1, 2, 3];
let mut iter = v.into_iter();
assert_eq!(Some(1), iter.next());
assert_eq!(Some(2), iter.next());
assert_eq!(Some(3), iter.next());
assert_eq!(None, iter.next());
Implementors
sourceimpl<'a> IntoIterator for &'a Map<String, Value>
impl<'a> IntoIterator for &'a Map<String, Value>
sourceimpl<'a> IntoIterator for &'a mut Map<String, Value>
impl<'a> IntoIterator for &'a mut Map<String, Value>
sourceimpl<'a, I> IntoIterator for &'a IntoChunks<I> where
I: Iterator,
<I as Iterator>::Item: 'a,
impl<'a, I> IntoIterator for &'a IntoChunks<I> where
I: Iterator,
<I as Iterator>::Item: 'a,
sourceimpl<'a, I> IntoIterator for &'a RcIter<I> where
I: Iterator,
impl<'a, I> IntoIterator for &'a RcIter<I> where
I: Iterator,
Return an iterator from &RcIter<I>
(by simply cloning it).
sourceimpl<'a, K, I, F> IntoIterator for &'a GroupBy<K, I, F> where
I: Iterator,
F: for<'_> FnMut(&<I as Iterator>::Item) -> K,
K: PartialEq<K>,
<I as Iterator>::Item: 'a,
impl<'a, K, I, F> IntoIterator for &'a GroupBy<K, I, F> where
I: Iterator,
F: for<'_> FnMut(&<I as Iterator>::Item) -> K,
K: PartialEq<K>,
<I as Iterator>::Item: 'a,
sourceimpl<'a, K, V, A> IntoIterator for &'a BTreeMap<K, V, A> where
A: Allocator + Clone,
impl<'a, K, V, A> IntoIterator for &'a BTreeMap<K, V, A> where
A: Allocator + Clone,
sourceimpl<'a, K, V, A> IntoIterator for &'a mut BTreeMap<K, V, A> where
A: Allocator + Clone,
impl<'a, K, V, A> IntoIterator for &'a mut BTreeMap<K, V, A> where
A: Allocator + Clone,
sourceimpl<'a, K, V, S> IntoIterator for &'a HashMap<K, V, S>
impl<'a, K, V, S> IntoIterator for &'a HashMap<K, V, S>
sourceimpl<'a, K, V, S> IntoIterator for &'a mut HashMap<K, V, S>
impl<'a, K, V, S> IntoIterator for &'a mut HashMap<K, V, S>
1.4.0 · sourceimpl<'a, T> IntoIterator for &'a Option<T>
impl<'a, T> IntoIterator for &'a Option<T>
sourceimpl<'a, T> IntoIterator for &'a BinaryHeap<T>
impl<'a, T> IntoIterator for &'a BinaryHeap<T>
sourceimpl<'a, T> IntoIterator for &'a LinkedList<T>
impl<'a, T> IntoIterator for &'a LinkedList<T>
1.4.0 · sourceimpl<'a, T> IntoIterator for &'a mut Option<T>
impl<'a, T> IntoIterator for &'a mut Option<T>
sourceimpl<'a, T> IntoIterator for &'a mut LinkedList<T>
impl<'a, T> IntoIterator for &'a mut LinkedList<T>
sourceimpl<'a, T, A> IntoIterator for &'a BTreeSet<T, A> where
A: Allocator + Clone,
impl<'a, T, A> IntoIterator for &'a BTreeSet<T, A> where
A: Allocator + Clone,
sourceimpl<'a, T, A> IntoIterator for &'a VecDeque<T, A> where
A: Allocator,
impl<'a, T, A> IntoIterator for &'a VecDeque<T, A> where
A: Allocator,
sourceimpl<'a, T, A> IntoIterator for &'a Vec<T, A> where
A: Allocator,
impl<'a, T, A> IntoIterator for &'a Vec<T, A> where
A: Allocator,
sourceimpl<'a, T, A> IntoIterator for &'a mut VecDeque<T, A> where
A: Allocator,
impl<'a, T, A> IntoIterator for &'a mut VecDeque<T, A> where
A: Allocator,
sourceimpl<'a, T, A> IntoIterator for &'a mut Vec<T, A> where
A: Allocator,
impl<'a, T, A> IntoIterator for &'a mut Vec<T, A> where
A: Allocator,
1.4.0 · sourceimpl<'a, T, E> IntoIterator for &'a Result<T, E>
impl<'a, T, E> IntoIterator for &'a Result<T, E>
1.4.0 · sourceimpl<'a, T, E> IntoIterator for &'a mut Result<T, E>
impl<'a, T, E> IntoIterator for &'a mut Result<T, E>
sourceimpl<'a, T, const CAP: usize> IntoIterator for &'a ArrayVec<T, CAP> where
T: 'a,
impl<'a, T, const CAP: usize> IntoIterator for &'a ArrayVec<T, CAP> where
T: 'a,
Iterate the ArrayVec
with references to each element.
use arrayvec::ArrayVec;
let array = ArrayVec::from([1, 2, 3]);
for elt in &array {
// ...
}
sourceimpl<'a, T, const CAP: usize> IntoIterator for &'a mut ArrayVec<T, CAP> where
T: 'a,
impl<'a, T, const CAP: usize> IntoIterator for &'a mut ArrayVec<T, CAP> where
T: 'a,
Iterate the ArrayVec
with mutable references to each element.
use arrayvec::ArrayVec;
let mut array = ArrayVec::from([1, 2, 3]);
for elt in &mut array {
// ...
}
sourceimpl<'a, T, const N: usize> IntoIterator for &'a [T; N]
impl<'a, T, const N: usize> IntoIterator for &'a [T; N]
sourceimpl<'a, T, const N: usize> IntoIterator for &'a mut [T; N]
impl<'a, T, const N: usize> IntoIterator for &'a mut [T; N]
const: unstable · sourceimpl<I> IntoIterator for I where
I: Iterator,
impl<I> IntoIterator for I where
I: Iterator,
sourceimpl<K, V, A> IntoIterator for BTreeMap<K, V, A> where
A: Allocator + Clone,
impl<K, V, A> IntoIterator for BTreeMap<K, V, A> where
A: Allocator + Clone,
sourceimpl<K, V, S> IntoIterator for HashMap<K, V, S>
impl<K, V, S> IntoIterator for HashMap<K, V, S>
sourceimpl<T> IntoIterator for BinaryHeap<T>
impl<T> IntoIterator for BinaryHeap<T>
sourceimpl<T> IntoIterator for LinkedList<T>
impl<T> IntoIterator for LinkedList<T>
sourceimpl<T, A> IntoIterator for BTreeSet<T, A> where
A: Allocator + Clone,
impl<T, A> IntoIterator for BTreeSet<T, A> where
A: Allocator + Clone,
sourceimpl<T, A> IntoIterator for VecDeque<T, A> where
A: Allocator,
impl<T, A> IntoIterator for VecDeque<T, A> where
A: Allocator,
sourceimpl<T, A> IntoIterator for Vec<T, A> where
A: Allocator,
impl<T, A> IntoIterator for Vec<T, A> where
A: Allocator,
sourceimpl<T, const CAP: usize> IntoIterator for ArrayVec<T, CAP>
impl<T, const CAP: usize> IntoIterator for ArrayVec<T, CAP>
Iterate the ArrayVec
with each element by value.
The vector is consumed by this operation.
use arrayvec::ArrayVec;
for elt in ArrayVec::from([1, 2, 3]) {
// ...
}