# 1.0.0[−][src]Struct core::iter::Chain

    #[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
    pub struct Chain<A, B> { /* fields omitted */ }

An iterator that strings two iterators together.

This `struct` is created by the `chain` method on `Iterator`. See its documentation for more.

## Trait Implementations

###

`impl<A: Clone, B: Clone> Clone for Chain<A, B>` | [src]

####
ⓘImportant traits for Chain<A, B>

### Important traits for Chain<A, B>

`impl<A, B> Iterator for Chain<A, B> where
A: Iterator,
B: Iterator<Item = A::Item>, type Item = A::Item;`

`fn clone(&self) -> Chain<A, B>` | [src]

Returns a copy of the value. Read more

####

`fn clone_from(&mut self, source: &Self)` | [src]

Performs copy-assignment from `source`. Read more

###

`impl<A, B> Iterator for Chain<A, B> where A: Iterator, B: Iterator<Item = A::Item>,` | [src]

#### `type Item = A::Item`

The type of the elements being iterated over.

####

`fn next(&mut self) -> Option<A::Item>` | [src]

Advances the iterator and returns the next value. Read more

####

`fn count(self) -> usize` | [src]

Consumes the iterator, counting the number of iterations and returning it. Read more

####

`fn try_fold<Acc, F, R>(&mut self, init: Acc, f: F) -> R where Self: Sized, F: FnMut(Acc, Self::Item) -> R, R: Try<Ok = Acc>,` | [src]

An iterator method that applies a function as long as it returns successfully, producing a single, final value. Read more

####

`fn fold<Acc, F>(self, init: Acc, f: F) -> Acc where F: FnMut(Acc, Self::Item) -> Acc,` | [src]

An iterator method that applies a function, producing a single, final value. Read more

####

`fn nth(&mut self, n: usize) -> Option<A::Item>` | [src]

Returns the `n`th element of the iterator. Read more

####

`fn find<P>(&mut self, predicate: P) -> Option<Self::Item> where P: FnMut(&Self::Item) -> bool,` | [src]

Searches for an element of an iterator that satisfies a predicate. Read more

####

`fn last(self) -> Option<A::Item>` | [src]

Consumes the iterator, returning the last element. Read more

####

`fn size_hint(&self) -> (usize, Option<usize>)` | [src]

Returns the bounds on the remaining length of the iterator. Read more

####
ⓘImportant traits for StepBy<I>

### Important traits for StepBy<I>

`impl<I> Iterator for StepBy<I> where
I: Iterator, type Item = I::Item;`

`fn step_by(self, step: usize) -> StepBy<Self> where Self: Sized,` | 1.28.0 [src]

Creates an iterator starting at the same point, but stepping by the given amount at each iteration. Read more

####
ⓘImportant traits for Chain<A, B>

### Important traits for Chain<A, B>

`impl<A, B> Iterator for Chain<A, B> where
A: Iterator,
B: Iterator<Item = A::Item>, type Item = A::Item;`

`fn chain<U>(self, other: U) -> Chain<Self, U::IntoIter> where Self: Sized, U: IntoIterator<Item = Self::Item>,` | [src]

Takes two iterators and creates a new iterator over both in sequence. Read more

####
ⓘImportant traits for Zip<A, B>

### Important traits for Zip<A, B>

`impl<A, B> Iterator for Zip<A, B> where
A: Iterator,
B: Iterator, type Item = (A::Item, B::Item);`

`fn zip<U>(self, other: U) -> Zip<Self, U::IntoIter> where Self: Sized, U: IntoIterator,` | [src]

'Zips up' two iterators into a single iterator of pairs. Read more

####
ⓘImportant traits for Map<I, F>

### Important traits for Map<I, F>

`impl<B, I: Iterator, F> Iterator for Map<I, F> where
F: FnMut(I::Item) -> B, type Item = B;`

`fn map<B, F>(self, f: F) -> Map<Self, F> where Self: Sized, F: FnMut(Self::Item) -> B,` | [src]

Takes a closure and creates an iterator which calls that closure on each element. Read more

####

`fn for_each<F>(self, f: F) where Self: Sized, F: FnMut(Self::Item),` | 1.21.0 [src]

Calls a closure on each element of an iterator. Read more

####
ⓘImportant traits for Filter<I, P>

### Important traits for Filter<I, P>

`impl<I: Iterator, P> Iterator for Filter<I, P> where
P: FnMut(&I::Item) -> bool, type Item = I::Item;`

`fn filter<P>(self, predicate: P) -> Filter<Self, P> where Self: Sized, P: FnMut(&Self::Item) -> bool,` | [src]

Creates an iterator which uses a closure to determine if an element should be yielded. Read more

####
ⓘImportant traits for FilterMap<I, F>

### Important traits for FilterMap<I, F>

`impl<B, I: Iterator, F> Iterator for FilterMap<I, F> where
F: FnMut(I::Item) -> Option<B>, type Item = B;`

`fn filter_map<B, F>(self, f: F) -> FilterMap<Self, F> where Self: Sized, F: FnMut(Self::Item) -> Option<B>,` | [src]

Creates an iterator that both filters and maps. Read more

####
ⓘImportant traits for Enumerate<I>

### Important traits for Enumerate<I>

`impl<I> Iterator for Enumerate<I> where
I: Iterator, type Item = (usize, <I as Iterator>::Item);`

`fn enumerate(self) -> Enumerate<Self> where Self: Sized,` | [src]

Creates an iterator which gives the current iteration count as well as the next value. Read more

####
ⓘImportant traits for Peekable<I>

### Important traits for Peekable<I>

`impl<I: Iterator> Iterator for Peekable<I> type Item = I::Item;`

`fn peekable(self) -> Peekable<Self> where Self: Sized,` | [src]

Creates an iterator which can use `peek` to look at the next element of the iterator without consuming it. Read more

####
ⓘImportant traits for SkipWhile<I, P>

### Important traits for SkipWhile<I, P>

`impl<I: Iterator, P> Iterator for SkipWhile<I, P> where
P: FnMut(&I::Item) -> bool, type Item = I::Item;`

`fn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P> where Self: Sized, P: FnMut(&Self::Item) -> bool,` | [src]

Creates an iterator that [`skip`]s elements based on a predicate. Read more

####
ⓘImportant traits for TakeWhile<I, P>

### Important traits for TakeWhile<I, P>

`impl<I: Iterator, P> Iterator for TakeWhile<I, P> where
P: FnMut(&I::Item) -> bool, type Item = I::Item;`

`fn take_while<P>(self, predicate: P) -> TakeWhile<Self, P> where Self: Sized, P: FnMut(&Self::Item) -> bool,` | [src]

Creates an iterator that yields elements based on a predicate. Read more

####
ⓘImportant traits for Skip<I>

### Important traits for Skip<I>

`impl<I> Iterator for Skip<I> where
I: Iterator, type Item = <I as Iterator>::Item;`

`fn skip(self, n: usize) -> Skip<Self> where Self: Sized,` | [src]

Creates an iterator that skips the first `n` elements. Read more

####
ⓘImportant traits for Take<I>

### Important traits for Take<I>

`impl<I> Iterator for Take<I> where
I: Iterator, type Item = <I as Iterator>::Item;`

`fn take(self, n: usize) -> Take<Self> where Self: Sized,` | [src]

Creates an iterator that yields its first `n` elements. Read more

####
ⓘImportant traits for Scan<I, St, F>

### Important traits for Scan<I, St, F>

`impl<B, I, St, F> Iterator for Scan<I, St, F> where
I: Iterator,
F: FnMut(&mut St, I::Item) -> Option<B>, type Item = B;`

`fn scan<St, B, F>(self, initial_state: St, f: F) -> Scan<Self, St, F> where Self: Sized, F: FnMut(&mut St, Self::Item) -> Option<B>,` | [src]

An iterator adaptor similar to [`fold`] that holds internal state and produces a new iterator. Read more

####
ⓘImportant traits for FlatMap<I, U, F>

### Important traits for FlatMap<I, U, F>

`impl<I: Iterator, U: IntoIterator, F> Iterator for FlatMap<I, U, F> where
F: FnMut(I::Item) -> U, type Item = U::Item;`

`fn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F> where Self: Sized, U: IntoIterator, F: FnMut(Self::Item) -> U,` | [src]

Creates an iterator that works like map, but flattens nested structure. Read more

####
ⓘImportant traits for Flatten<I>

### Important traits for Flatten<I>

`impl<I, U> Iterator for Flatten<I> where
I: Iterator,
U: Iterator,
I::Item: IntoIterator<IntoIter = U, Item = U::Item>, type Item = U::Item;`

`fn flatten(self) -> Flatten<Self> where Self: Sized, Self::Item: IntoIterator,` | 1.29.0 [src]

Creates an iterator that flattens nested structure. Read more

####
ⓘImportant traits for Fuse<I>

### Important traits for Fuse<I>

`impl<I> Iterator for Fuse<I> where
I: Iterator, type Item = <I as Iterator>::Item;impl<I> Iterator for Fuse<I> where
I: FusedIterator,`

`fn fuse(self) -> Fuse<Self> where Self: Sized,` | [src]

Creates an iterator which ends after the first [`None`]. Read more

####
ⓘImportant traits for Inspect<I, F>

### Important traits for Inspect<I, F>

`impl<I: Iterator, F> Iterator for Inspect<I, F> where
F: FnMut(&I::Item), type Item = I::Item;`

`fn inspect<F>(self, f: F) -> Inspect<Self, F> where Self: Sized, F: FnMut(&Self::Item),` | [src]

Do something with each element of an iterator, passing the value on. Read more

####

`fn by_ref(&mut self) -> &mut Self where Self: Sized,` | [src]

Borrows an iterator, rather than consuming it. Read more

####

`#[must_use = "if you really need to exhaust the iterator, consider `.for_each(drop)` instead"] fn collect<B: FromIterator<Self::Item>>(self) -> B where Self: Sized,` | [src]

Transforms an iterator into a collection. Read more

####

`fn partition<B, F>(self, f: F) -> (B, B) where Self: Sized, B: Default + Extend<Self::Item>, F: FnMut(&Self::Item) -> bool,` | [src]

Consumes an iterator, creating two collections from it. Read more

####

`fn try_for_each<F, R>(&mut self, f: F) -> R where Self: Sized, F: FnMut(Self::Item) -> R, R: Try<Ok = ()>,` | 1.27.0 [src]

An iterator method that applies a fallible function to each item in the iterator, stopping at the first error and returning that error. Read more

####

`fn all<F>(&mut self, f: F) -> bool where Self: Sized, F: FnMut(Self::Item) -> bool,` | [src]

Tests if every element of the iterator matches a predicate. Read more

####

`fn any<F>(&mut self, f: F) -> bool where Self: Sized, F: FnMut(Self::Item) -> bool,` | [src]

Tests if any element of the iterator matches a predicate. Read more

####

`fn find_map<B, F>(&mut self, f: F) -> Option<B> where Self: Sized, F: FnMut(Self::Item) -> Option<B>,` | 1.30.0 [src]

Applies function to the elements of iterator and returns the first non-none result. Read more

####

`fn position<P>(&mut self, predicate: P) -> Option<usize> where Self: Sized, P: FnMut(Self::Item) -> bool,` | [src]

Searches for an element in an iterator, returning its index. Read more

####

`fn rposition<P>(&mut self, predicate: P) -> Option<usize> where P: FnMut(Self::Item) -> bool, Self: Sized + ExactSizeIterator + DoubleEndedIterator,` | [src]

Searches for an element in an iterator from the right, returning its index. Read more

####

`fn max(self) -> Option<Self::Item> where Self: Sized, Self::Item: Ord,` | [src]

Returns the maximum element of an iterator. Read more

####

`fn min(self) -> Option<Self::Item> where Self: Sized, Self::Item: Ord,` | [src]

Returns the minimum element of an iterator. Read more

####

`fn max_by_key<B: Ord, F>(self, f: F) -> Option<Self::Item> where Self: Sized, F: FnMut(&Self::Item) -> B,` | 1.6.0 [src]

Returns the element that gives the maximum value from the specified function. Read more

####

`fn max_by<F>(self, compare: F) -> Option<Self::Item> where Self: Sized, F: FnMut(&Self::Item, &Self::Item) -> Ordering,` | 1.15.0 [src]

Returns the element that gives the maximum value with respect to the specified comparison function. Read more

####

`fn min_by_key<B: Ord, F>(self, f: F) -> Option<Self::Item> where Self: Sized, F: FnMut(&Self::Item) -> B,` | 1.6.0 [src]

Returns the element that gives the minimum value from the specified function. Read more

####

`fn min_by<F>(self, compare: F) -> Option<Self::Item> where Self: Sized, F: FnMut(&Self::Item, &Self::Item) -> Ordering,` | 1.15.0 [src]

Returns the element that gives the minimum value with respect to the specified comparison function. Read more

####
ⓘImportant traits for Rev<I>

### Important traits for Rev<I>

`impl<I> Iterator for Rev<I> where
I: DoubleEndedIterator, type Item = <I as Iterator>::Item;`

`fn rev(self) -> Rev<Self> where Self: Sized + DoubleEndedIterator,` | [src]

Reverses an iterator's direction. Read more

####

`fn unzip<A, B, FromA, FromB>(self) -> (FromA, FromB) where FromA: Default + Extend<A>, FromB: Default + Extend<B>, Self: Sized + Iterator<Item = (A, B)>,` | [src]

Converts an iterator of pairs into a pair of containers. Read more

####
ⓘImportant traits for Copied<I>

### Important traits for Copied<I>

`impl<'a, I, T: 'a> Iterator for Copied<I> where
I: Iterator<Item = &'a T>,
T: Copy, type Item = T;`

`fn copied<'a, T: 'a>(self) -> Copied<Self> where Self: Sized + Iterator<Item = &'a T>, T: Copy,` | [src]

🔬 This is a nightly-only experimental API. (`iter_copied` #57127)

Creates an iterator which copies all of its elements. Read more

####
ⓘImportant traits for Cloned<I>

### Important traits for Cloned<I>

`impl<'a, I, T: 'a> Iterator for Cloned<I> where
I: Iterator<Item = &'a T>,
T: Clone, type Item = T;`

`fn cloned<'a, T: 'a>(self) -> Cloned<Self> where Self: Sized + Iterator<Item = &'a T>, T: Clone,` | [src]

Creates an iterator which [`clone`]s all of its elements. Read more

####
ⓘImportant traits for Cycle<I>

### Important traits for Cycle<I>

`impl<I> Iterator for Cycle<I> where
I: Clone + Iterator, type Item = <I as Iterator>::Item;`

`fn cycle(self) -> Cycle<Self> where Self: Sized + Clone,` | [src]

Repeats an iterator endlessly. Read more

####

`fn sum<S>(self) -> S where Self: Sized, S: Sum<Self::Item>,` | 1.11.0 [src]

Sums the elements of an iterator. Read more

####

`fn product<P>(self) -> P where Self: Sized, P: Product<Self::Item>,` | 1.11.0 [src]

Iterates over the entire iterator, multiplying all the elements Read more

####

`fn cmp<I>(self, other: I) -> Ordering where I: IntoIterator<Item = Self::Item>, Self::Item: Ord, Self: Sized,` | 1.5.0 [src]

Lexicographically compares the elements of this `Iterator` with those of another. Read more

####

`fn partial_cmp<I>(self, other: I) -> Option<Ordering> where I: IntoIterator, Self::Item: PartialOrd<I::Item>, Self: Sized,` | 1.5.0 [src]

Lexicographically compares the elements of this `Iterator` with those of another. Read more

####

`fn eq<I>(self, other: I) -> bool where I: IntoIterator, Self::Item: PartialEq<I::Item>, Self: Sized,` | 1.5.0 [src]

Determines if the elements of this `Iterator` are equal to those of another. Read more

####

`fn ne<I>(self, other: I) -> bool where I: IntoIterator, Self::Item: PartialEq<I::Item>, Self: Sized,` | 1.5.0 [src]

Determines if the elements of this `Iterator` are unequal to those of another. Read more

####

`fn lt<I>(self, other: I) -> bool where I: IntoIterator, Self::Item: PartialOrd<I::Item>, Self: Sized,` | 1.5.0 [src]

Determines if the elements of this `Iterator` are lexicographically less than those of another. Read more

####

`fn le<I>(self, other: I) -> bool where I: IntoIterator, Self::Item: PartialOrd<I::Item>, Self: Sized,` | 1.5.0 [src]

Determines if the elements of this `Iterator` are lexicographically less or equal to those of another. Read more

####

`fn gt<I>(self, other: I) -> bool where I: IntoIterator, Self::Item: PartialOrd<I::Item>, Self: Sized,` | 1.5.0 [src]

Determines if the elements of this `Iterator` are lexicographically greater than those of another. Read more

####

`fn ge<I>(self, other: I) -> bool where I: IntoIterator, Self::Item: PartialOrd<I::Item>, Self: Sized,` | 1.5.0 [src]

Determines if the elements of this `Iterator` are lexicographically greater than or equal to those of another. Read more

###

`impl<A, B> DoubleEndedIterator for Chain<A, B> where A: DoubleEndedIterator, B: DoubleEndedIterator<Item = A::Item>,` | [src]

####

`fn next_back(&mut self) -> Option<A::Item>` | [src]

Removes and returns an element from the end of the iterator. Read more

####

`fn try_rfold<Acc, F, R>(&mut self, init: Acc, f: F) -> R where Self: Sized, F: FnMut(Acc, Self::Item) -> R, R: Try<Ok = Acc>,` | [src]

This is the reverse version of [`try_fold()`]: it takes elements starting from the back of the iterator. Read more

####

`fn rfold<Acc, F>(self, init: Acc, f: F) -> Acc where F: FnMut(Acc, Self::Item) -> Acc,` | [src]

An iterator method that reduces the iterator's elements to a single, final value, starting from the back. Read more

####

`fn nth_back(&mut self, n: usize) -> Option<Self::Item>` | [src]

🔬 This is a nightly-only experimental API. (`iter_nth_back` #56995)

Returns the `n`th element from the end of the iterator. Read more

####

`fn rfind<P>(&mut self, predicate: P) -> Option<Self::Item> where Self: Sized, P: FnMut(&Self::Item) -> bool,` | 1.27.0 [src]

Searches for an element of an iterator from the back that satisfies a predicate. Read more

###

`impl<A, B> FusedIterator for Chain<A, B> where A: FusedIterator, B: FusedIterator<Item = A::Item>,` | 1.26.0 [src]

###

`impl<A, B> TrustedLen for Chain<A, B> where A: TrustedLen, B: TrustedLen<Item = A::Item>,` | [src]

###

`impl<A: Debug, B: Debug> Debug for Chain<A, B>` | [src]

####

`fn fmt(&self, f: &mut Formatter) -> Result` | [src]

Formats the value using the given formatter. Read more

## Auto Trait Implementations

###

`impl<A, B> Send for Chain<A, B> where A: Send, B: Send,` |

###

`impl<A, B> Sync for Chain<A, B> where A: Sync, B: Sync,` |

## Blanket Implementations

###

`impl<T, U> Into for T where U: From<T>,` | [src]

####

`fn into(Self) -> U` | [src]

Performs the conversion.

###

`impl<T> From for T` | [src]

####

`fn from(T) -> T` | [src]

Performs the conversion.

###

`impl<T, U> TryInto for T where U: TryFrom<T>,` | [src]

#### `type Error = <U as TryFrom<T>>::Error`

🔬 This is a nightly-only experimental API. (`try_from` #33417)

The type returned in the event of a conversion error.

####

`fn try_into(Self) -> Result<U, <U as TryFrom<T>>::Error>` | [src]

🔬 This is a nightly-only experimental API. (`try_from` #33417)

Performs the conversion.

###

`impl<T, U> TryFrom for T where T: From<U>,` | [src]

#### `type Error = !`

🔬 This is a nightly-only experimental API. (`try_from` #33417)

The type returned in the event of a conversion error.

####

`fn try_from(U) -> Result<T, <T as TryFrom<U>>::Error>` | [src]

🔬 This is a nightly-only experimental API. (`try_from` #33417)

Performs the conversion.

###

`impl<T> Borrow for T where T: ?Sized,` | [src]

####

`fn borrow(&Self) -> &T` | [src]

Immutably borrows from an owned value. Read more

###

`impl<T> BorrowMut for T where T: ?Sized,` | [src]

####

`fn borrow_mut(&mut Self) -> &mut T` | [src]

Mutably borrows from an owned value. Read more

###

`impl<T> Any for T where T: 'static + ?Sized,` | [src]

####

`fn get_type_id(&Self) -> TypeId` | [src]

🔬 This is a nightly-only experimental API. (`get_type_id` #27745)

this method will likely be replaced by an associated static

Gets the `TypeId` of `self`. Read more

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