Trait nom::lib::std::prelude::v1::rust_2021::IntoIterator

[+] Show declaration

pub trait IntoIterator {
    type Item;
    type IntoIter: Iterator;
[+] Expand attributes
#[lang = "into_iter"]    pub 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 = vec![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()
}

Associated Types

type Item[−]

The type of the elements being iterated over.

type IntoIter: Iterator[−]

Which kind of iterator are we turning this into?

Required methods

[+] Expand attributes

#[lang = "into_iter"]pub fn into_iter(self) -> Self::IntoIter[−]

Creates an iterator from a value.

See the module-level documentation for more.

Examples

Basic usage:

let v = vec![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());

Implementations on Foreign Types

impl<'a, T> IntoIterator for &'a Receiver<T>[−]

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type Item = T

type IntoIter = Iter<'a, T>

pub fn into_iter(self) -> Iter<'a, T>

impl<'a> IntoIterator for &'a UnixListener[−]

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type Item = Result<UnixStream, Error>

type IntoIter = Incoming<'a>

pub fn into_iter(self) -> Incoming<'a>

impl<'a> IntoIterator for &'a PathBuf[−]

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type Item = &'a OsStr

type IntoIter = Iter<'a>

pub fn into_iter(self) -> Iter<'a>

impl<'a> IntoIterator for &'a Path[−]

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type Item = &'a OsStr

type IntoIter = Iter<'a>

pub fn into_iter(self) -> Iter<'a>

impl<T> IntoIterator for Receiver<T>[−]

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type Item = T

type IntoIter = IntoIter<T>

pub fn into_iter(self) -> IntoIter<T>

impl<'a, T> IntoIterator for &'a [T][−]

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type Item = &'a T

type IntoIter = Iter<'a, T>

pub fn into_iter(self) -> Iter<'a, T>

impl<'a, T> IntoIterator for &'a mut [T][−]

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type Item = &'a mut T

type IntoIter = IterMut<'a, T>

pub fn into_iter(self) -> IterMut<'a, T>

impl<'a, T, const N: usize> IntoIterator for &'a [T; N][−]

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type Item = &'a T

type IntoIter = Iter<'a, T>

pub fn into_iter(self) -> Iter<'a, T>

impl<'a, T, const N: usize> IntoIterator for &'a mut [T; N][−]

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type Item = &'a mut T

type IntoIter = IterMut<'a, T>

pub fn into_iter(self) -> IterMut<'a, T>

Implementors

impl<'a, K, V> IntoIterator for &'a BTreeMap<K, V>[+]

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type Item = (&'a K, &'a V)

type IntoIter = Iter<'a, K, V>

pub fn into_iter(self) -> Iter<'a, K, V>

impl<'a, K, V> IntoIterator for &'a mut BTreeMap<K, V>[+]

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type Item = (&'a K, &'a mut V)

type IntoIter = IterMut<'a, K, V>

pub fn into_iter(self) -> IterMut<'a, K, V>

impl<'a, K, V, S> IntoIterator for &'a HashMap<K, V, S>[+]

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type Item = (&'a K, &'a V)

type IntoIter = Iter<'a, K, V>

pub fn into_iter(self) -> Iter<'a, K, V>

impl<'a, K, V, S> IntoIterator for &'a mut HashMap<K, V, S>[+]

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type Item = (&'a K, &'a mut V)

type IntoIter = IterMut<'a, K, V>

pub fn into_iter(self) -> IterMut<'a, K, V>

impl<'a, T> IntoIterator for &'a Option<T>[+]

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type Item = &'a T

type IntoIter = Iter<'a, T>

pub fn into_iter(self) -> Iter<'a, T>

impl<'a, T> IntoIterator for &'a BTreeSet<T>[+]

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type Item = &'a T

type IntoIter = Iter<'a, T>

pub fn into_iter(self) -> Iter<'a, T>

impl<'a, T> IntoIterator for &'a BinaryHeap<T>[+]

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type Item = &'a T

type IntoIter = Iter<'a, T>

pub fn into_iter(self) -> Iter<'a, T>

impl<'a, T> IntoIterator for &'a LinkedList<T>[+]

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type Item = &'a T

type IntoIter = Iter<'a, T>

pub fn into_iter(self) -> Iter<'a, T>

impl<'a, T> IntoIterator for &'a VecDeque<T>[+]

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type Item = &'a T

type IntoIter = Iter<'a, T>

pub fn into_iter(self) -> Iter<'a, T>

impl<'a, T> IntoIterator for &'a mut Option<T>[+]

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type Item = &'a mut T

type IntoIter = IterMut<'a, T>

pub fn into_iter(self) -> IterMut<'a, T>

impl<'a, T> IntoIterator for &'a mut LinkedList<T>[+]

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type Item = &'a mut T

type IntoIter = IterMut<'a, T>

pub fn into_iter(self) -> IterMut<'a, T>

impl<'a, T> IntoIterator for &'a mut VecDeque<T>[+]

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type Item = &'a mut T

type IntoIter = IterMut<'a, T>

pub fn into_iter(self) -> IterMut<'a, T>

impl<'a, T, A> IntoIterator for &'a Vec<T, A> where
    A: Allocator, [+]

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type Item = &'a T

type IntoIter = Iter<'a, T>

pub fn into_iter(self) -> Iter<'a, T>

impl<'a, T, A> IntoIterator for &'a mut Vec<T, A> where
    A: Allocator, [+]

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type Item = &'a mut T

type IntoIter = IterMut<'a, T>

pub fn into_iter(self) -> IterMut<'a, T>

impl<'a, T, E> IntoIterator for &'a Result<T, E>[+]

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type Item = &'a T

type IntoIter = Iter<'a, T>

pub fn into_iter(self) -> Iter<'a, T>

impl<'a, T, E> IntoIterator for &'a mut Result<T, E>[+]

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type Item = &'a mut T

type IntoIter = IterMut<'a, T>

pub fn into_iter(self) -> IterMut<'a, T>

impl<'a, T, S> IntoIterator for &'a HashSet<T, S>[+]

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type Item = &'a T

type IntoIter = Iter<'a, T>

pub fn into_iter(self) -> Iter<'a, T>

impl<I> IntoIterator for I where
    I: Iterator, [+]

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type Item = <I as Iterator>::Item

type IntoIter = I

pub fn into_iter(self) -> I

impl<K, V> IntoIterator for BTreeMap<K, V>[+]

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type Item = (K, V)

type IntoIter = IntoIter<K, V>

pub fn into_iter(self) -> IntoIter<K, V>

impl<K, V, S> IntoIterator for HashMap<K, V, S>[+]

type Item = (K, V)

type IntoIter = IntoIter<K, V>

pub fn into_iter(self) -> IntoIter<K, V>[−]

Creates a consuming iterator, that is, one that moves each key-value pair out of the map in arbitrary order. The map cannot be used after calling this.

Examples

use std::collections::HashMap;

let mut map = HashMap::new();
map.insert("a", 1);
map.insert("b", 2);
map.insert("c", 3);

// Not possible with .iter()
let vec: Vec<(&str, i32)> = map.into_iter().collect();

impl<T> IntoIterator for Option<T>[+]

type Item = T

type IntoIter = IntoIter<T>

pub fn into_iter(self) -> IntoIter<T>[−]

Returns a consuming iterator over the possibly contained value.

Examples

let x = Some("string");
let v: Vec<&str> = x.into_iter().collect();
assert_eq!(v, ["string"]);

let x = None;
let v: Vec<&str> = x.into_iter().collect();
assert!(v.is_empty());

impl<T> IntoIterator for BTreeSet<T>[+]

type Item = T

type IntoIter = IntoIter<T>

pub fn into_iter(self) -> IntoIter<T>[−]

Gets an iterator for moving out the BTreeSet’s contents.

Examples

use std::collections::BTreeSet;

let set: BTreeSet<usize> = [1, 2, 3, 4].iter().cloned().collect();

let v: Vec<_> = set.into_iter().collect();
assert_eq!(v, [1, 2, 3, 4]);

impl<T> IntoIterator for BinaryHeap<T>[+]

type Item = T

type IntoIter = IntoIter<T>

pub fn into_iter(self) -> IntoIter<T>[−]

Creates a consuming iterator, that is, one that moves each value out of the binary heap in arbitrary order. The binary heap cannot be used after calling this.

Examples

Basic usage:

use std::collections::BinaryHeap;
let heap = BinaryHeap::from(vec![1, 2, 3, 4]);

// Print 1, 2, 3, 4 in arbitrary order
for x in heap.into_iter() {
    // x has type i32, not &i32
    println!("{}", x);
}

impl<T> IntoIterator for LinkedList<T>[+]

type Item = T

type IntoIter = IntoIter<T>

pub fn into_iter(self) -> IntoIter<T>[−]

Consumes the list into an iterator yielding elements by value.

impl<T> IntoIterator for VecDeque<T>[+]

type Item = T

type IntoIter = IntoIter<T>

pub fn into_iter(self) -> IntoIter<T>[−]

Consumes the VecDeque into a front-to-back iterator yielding elements by value.

impl<T, A> IntoIterator for Vec<T, A> where
    A: Allocator, [+]

type Item = T

type IntoIter = IntoIter<T, A>

pub fn into_iter(self) -> IntoIter<T, A>[−]

Creates a consuming iterator, that is, one that moves each value out of the vector (from start to end). The vector cannot be used after calling this.

Examples

let v = vec!["a".to_string(), "b".to_string()];
for s in v.into_iter() {
    // s has type String, not &String
    println!("{}", s);
}

impl<T, E> IntoIterator for Result<T, E>[+]

type Item = T

type IntoIter = IntoIter<T>

pub fn into_iter(self) -> IntoIter<T>[−]

Returns a consuming iterator over the possibly contained value.

The iterator yields one value if the result is Result::Ok, otherwise none.

Examples

Basic usage:

let x: Result<u32, &str> = Ok(5);
let v: Vec<u32> = x.into_iter().collect();
assert_eq!(v, [5]);

let x: Result<u32, &str> = Err("nothing!");
let v: Vec<u32> = x.into_iter().collect();
assert_eq!(v, []);

impl<T, S> IntoIterator for HashSet<T, S>[+]

type Item = T

type IntoIter = IntoIter<T>

pub fn into_iter(self) -> IntoIter<T>[−]

Creates a consuming iterator, that is, one that moves each value out of the set in arbitrary order. The set cannot be used after calling this.

Examples

use std::collections::HashSet;
let mut set = HashSet::new();
set.insert("a".to_string());
set.insert("b".to_string());

// Not possible to collect to a Vec<String> with a regular `.iter()`.
let v: Vec<String> = set.into_iter().collect();

// Will print in an arbitrary order.
for x in &v {
    println!("{}", x);
}

impl<'a, K, V, S> IntoIterator for &'a AHashMap<K, V, S>

impl<'a, K, V, S> IntoIterator for &'a mut AHashMap<K, V, S>

impl<K, V, S> IntoIterator for AHashMap<K, V, S>

impl<'a, T, S> IntoIterator for &'a AHashSet<T, S>

impl<T, S> IntoIterator for AHashSet<T, S>

impl<'a, A: Array> IntoIterator for &'a ArrayVec<A>

impl<'a, A: Array> IntoIterator for &'a mut ArrayVec<A>

impl<A: Array> IntoIterator for ArrayVec<A>

impl<T, U> IntoIterator for Chain<T, U> where     T: Buf,     U: Buf,

impl IntoIterator for Bytes

impl<'a> IntoIterator for &'a Bytes

impl IntoIterator for BytesMut

impl<'a> IntoIterator for &'a BytesMut

impl<'a, T> IntoIterator for &'a Receiver<T>

impl<T> IntoIterator for Receiver<T>

impl<K, V> IntoIterator for SkipList<K, V>

impl<K, V> IntoIterator for SkipMap<K, V>

impl<'a, K, V> IntoIterator for &'a SkipMap<K, V> where     K: Ord,

impl<T> IntoIterator for SkipSet<T>

impl<'a, T> IntoIterator for &'a SkipSet<T> where     T: Ord,

impl<T> IntoIterator for Fields<T>

impl IntoIterator for Error

impl<'a, K: Eq + Hash, S: BuildHasher + Clone> IntoIterator for DashSet<K, S>

impl<'a, K: Eq + Hash, V, S: BuildHasher + Clone> IntoIterator for DashMap<K, V, S>

impl<'a, K: Eq + Hash, V, S: BuildHasher + Clone> IntoIterator for &'a DashMap<K, V, S>

impl<T, N> IntoIterator for GenericArray<T, N> where     N: ArrayLength<T>,

impl<'a, T: 'a, N> IntoIterator for &'a GenericArray<T, N> where     N: ArrayLength<T>,

impl<'a, T: 'a, N> IntoIterator for &'a mut GenericArray<T, N> where     N: ArrayLength<T>,

impl<'a> IntoIterator for &'a AuthContext

impl<'a> IntoIterator for &'a Metadata

impl<'a, T> IntoIterator for &'a HeaderMap<T>

impl<'a, T> IntoIterator for &'a mut HeaderMap<T>

impl<T> IntoIterator for HeaderMap<T>

impl<'a, T> IntoIterator for GetAll<'a, T>

impl<'a, 'b: 'a, T> IntoIterator for &'b GetAll<'a, T>

impl<'a, T> IntoIterator for OccupiedEntry<'a, T>

impl<'a, 'b: 'a, T> IntoIterator for &'b OccupiedEntry<'a, T>

impl<'a, 'b: 'a, T> IntoIterator for &'b mut OccupiedEntry<'a, T>

impl<'a, T, S> IntoIterator for &'a IndexSet<T, S> where     T: Hash + Eq,     S: BuildHasher,

impl<T, S> IntoIterator for IndexSet<T, S> where     T: Hash + Eq,     S: BuildHasher,

impl<'a, K, V, S> IntoIterator for &'a IndexMap<K, V, S> where     K: Hash + Eq,     S: BuildHasher,

impl<'a, K, V, S> IntoIterator for &'a mut IndexMap<K, V, S> where     K: Hash + Eq,     S: BuildHasher,

impl<K, V, S> IntoIterator for IndexMap<K, V, S> where     K: Hash + Eq,     S: BuildHasher,

impl<'a, K, I, F> IntoIterator for &'a GroupBy<K, I, F> where     I: Iterator,     I::Item: 'a,     F: FnMut(&I::Item) -> K,     K: PartialEq,

impl<'a, I> IntoIterator for &'a IntoChunks<I> where     I: Iterator,     I::Item: 'a,

impl<'a, I> IntoIterator for &'a RcIter<I> where     I: Iterator,

impl<'a, K: Hash + Eq, V, S: BuildHasher> IntoIterator for &'a LinkedHashMap<K, V, S>

impl<'a, K: Hash + Eq, V, S: BuildHasher> IntoIterator for &'a mut LinkedHashMap<K, V, S>

impl<K: Hash + Eq, V, S: BuildHasher> IntoIterator for LinkedHashMap<K, V, S>

impl<'a, T, S> IntoIterator for &'a LinkedHashSet<T, S> where     T: Eq + Hash,     S: BuildHasher,

impl<T, S> IntoIterator for LinkedHashSet<T, S> where     T: Eq + Hash,     S: BuildHasher,

impl IntoIterator for MimeGuess

impl<'a> IntoIterator for &'a MimeGuess

impl<'a> IntoIterator for &'a Events

impl IntoIterator for Events

impl<T: Stackable> IntoIterator for Stack<T>

impl<'a, T: Stackable> IntoIterator for &'a StackRef<T>

impl<'a, T: Stackable> IntoIterator for &'a mut StackRef<T>

impl<'a, T: Stackable> IntoIterator for &'a Stack<T>

impl<'a, T: Stackable> IntoIterator for &'a mut Stack<T>

impl IntoIterator for TokenStream

impl<'a, T> IntoIterator for &'a RepeatedField<T>

impl<'a, T> IntoIterator for &'a SingularField<T>

impl<'a, T> IntoIterator for &'a SingularPtrField<T>

impl<'a> IntoIterator for &'a UnknownValues

impl<'a> IntoIterator for &'a UnknownFields

impl IntoIterator for IndexVec

impl IntoIterator for SetMatches

impl<'a> IntoIterator for &'a SetMatches

impl IntoIterator for SetMatches

impl<'a> IntoIterator for &'a SetMatches

impl<'a> IntoIterator for &'a Utf8Sequence

impl<'a> IntoIterator for &'a TablePropertiesCollectionView

impl<'a> IntoIterator for &'a UserCollectedProperties

impl<'a> IntoIterator for &'a History

impl<'a> IntoIterator for &'a Map<String, Value>

impl<'a> IntoIterator for &'a mut Map<String, Value>

impl IntoIterator for Map<String, Value>

impl<'a, T> IntoIterator for &'a Slab<T>

impl<'a, T> IntoIterator for &'a mut Slab<T>

impl<A: Array> IntoIterator for SmallVec<A>

impl<'a, A: Array> IntoIterator for &'a SmallVec<A>

impl<'a, A: Array> IntoIterator for &'a mut SmallVec<A>

impl<'a> IntoIterator for &'a StrStack

impl IntoIterator for Fields

impl<'a> IntoIterator for &'a Fields

impl<'a> IntoIterator for &'a mut Fields

impl<T, P> IntoIterator for Punctuated<T, P>

impl<'a, T, P> IntoIterator for &'a Punctuated<T, P>

impl<'a, T, P> IntoIterator for &'a mut Punctuated<T, P>

impl IntoIterator for Error

impl<'a> IntoIterator for &'a Error

impl<'a> IntoIterator for &'a Networks

impl<T: Send> IntoIterator for CachedThreadLocal<T>

impl<'a, T: Send + 'a> IntoIterator for &'a mut CachedThreadLocal<T>

impl<T: Send> IntoIterator for ThreadLocal<T>

impl<'a, T: Send + 'a> IntoIterator for &'a mut ThreadLocal<T>

impl<'a> IntoIterator for LogicalRows<'a>

impl<'a> IntoIterator for &'a Map<String, Value>

impl<'a> IntoIterator for &'a mut Map<String, Value>

impl IntoIterator for Map<String, Value>

impl<'a> IntoIterator for &'a FieldSet

impl<T> IntoIterator for VecMap<T>

impl<'a, T> IntoIterator for &'a VecMap<T>

impl<'a, T> IntoIterator for &'a mut VecMap<T>

impl IntoIterator for WalkDir

impl<'a> IntoIterator for &'a Namespace

impl<'a> IntoIterator for &'a NamespaceStack

impl<R: Read> IntoIterator for EventReader<R>