std::ops::Range - Rust
Description: API documentation for the Rust `Range` struct in crate `std`.
Keywords: rust, rustlang, rust-lang, Range

# 1.0.0[−][src]Struct std::ops::Range

    pub struct Range<Idx> {
        pub start: Idx,
        pub end: Idx,
    }

A (half-open) range bounded inclusively below and exclusively above (`start..end`).

The `Range` `start..end` contains all values with `x >= start` and `x < end`. It is empty unless `start < end`.

# Examples

    assert_eq!((3..5), std::ops::Range { start: 3, end: 5 });
    assert_eq!(3 + 4 + 5, (3..6).sum());

    let arr = ['a', 'b', 'c', 'd'];
    assert_eq!(arr[ .. ], ['a', 'b', 'c', 'd']);
    assert_eq!(arr[ ..3], ['a', 'b', 'c',    ]);
    assert_eq!(arr[1.. ], [     'b', 'c', 'd']);
    assert_eq!(arr[1..3], [     'b', 'c'     ]);  // RangeRun

## Fields

`start: Idx`

The lower bound of the range (inclusive).

`end: Idx`

The upper bound of the range (exclusive).

## Methods

### `impl<Idx> Range<Idx> where
Idx: PartialOrd<Idx>,` [src]

#### `pub fn contains<U>(&self, item: &U) -> bool where
Idx: PartialOrd<U>,
U: PartialOrd<Idx> + ?Sized,` [src]

🔬 This is a nightly-only experimental API. (`range_contains` #32311)

recently added as per RFC

Returns `true` if `item` is contained in the range.

# Examples

    #![feature(range_contains)]

    use std::f32;

    assert!(!(3..5).contains(&2));
    assert!( (3..5).contains(&3));
    assert!( (3..5).contains(&4));
    assert!(!(3..5).contains(&5));

    assert!(!(3..3).contains(&3));
    assert!(!(3..2).contains(&3));

    assert!( (0.0..1.0).contains(&0.5));
    assert!(!(0.0..1.0).contains(&f32::NAN));
    assert!(!(0.0..f32::NAN).contains(&0.5));
    assert!(!(f32::NAN..1.0).contains(&0.5));Run

#### `pub fn is_empty(&self) -> bool`[src]

🔬 This is a nightly-only experimental API. (`range_is_empty` #48111)

recently added

Returns `true` if the range contains no items.

# Examples

    #![feature(range_is_empty)]

    assert!(!(3..5).is_empty());
    assert!( (3..3).is_empty());
    assert!( (3..2).is_empty());Run

The range is empty if either side is incomparable:

    #![feature(range_is_empty)]

    use std::f32::NAN;
    assert!(!(3.0..5.0).is_empty());
    assert!( (3.0..NAN).is_empty());
    assert!( (NAN..5.0).is_empty());Run

## Trait Implementations

### `impl<A> Iterator for Range<A> where
A: Step,` [src]

#### `type Item = A`

The type of the elements being iterated over.

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

Advances the iterator and returns the next value. Read more

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

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

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

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

#### `fn last(self) -> Option<A>`[src]

Consumes the iterator, returning the last element. Read more

#### `fn min(self) -> Option<A>`[src]

Returns the minimum element of an iterator. Read more

#### `fn max(self) -> Option<A>`[src]

Returns the maximum element of an iterator. Read more

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

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

####
ⓘImportant traits for StepBy<I>

### Important traits for StepBy<I>

`impl<I> Iterator for StepBy<I> where
I: Iterator, type Item = <I as Iterator>::Item;`
`fn step_by(self, step: usize) -> StepBy<Self>`
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 as Iterator>::Item>, type Item = <A as Iterator>::Item;`
`fn chain<U>(self, other: U) -> Chain<Self, <U as IntoIterator>::IntoIter> where
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 as Iterator>::Item, <B as Iterator>::Item);`
`fn zip<U>(self, other: U) -> Zip<Self, <U as IntoIterator>::IntoIter> where
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, F> Iterator for Map<I, F> where
F: FnMut(<I as Iterator>::Item) -> B,
I: Iterator, type Item = B;`
`fn map<B, F>(self, f: F) -> Map<Self, F> where
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
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, P> Iterator for Filter<I, P> where
I: Iterator,
P: FnMut(&<I as Iterator>::Item) -> bool, type Item = <I as Iterator>::Item;`
`fn filter<P>(self, predicate: P) -> Filter<Self, P> where
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, F> Iterator for FilterMap<I, F> where
F: FnMut(<I as Iterator>::Item) -> Option<B>,
I: Iterator, type Item = B;`
`fn filter_map<B, F>(self, f: F) -> FilterMap<Self, F> where
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>`[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 for Peekable<I> where
I: Iterator, type Item = <I as Iterator>::Item;`
`fn peekable(self) -> Peekable<Self>`[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, P> Iterator for SkipWhile<I, P> where
I: Iterator,
P: FnMut(&<I as Iterator>::Item) -> bool, type Item = <I as Iterator>::Item;`
`fn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P> where
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, P> Iterator for TakeWhile<I, P> where
I: Iterator,
P: FnMut(&<I as Iterator>::Item) -> bool, type Item = <I as Iterator>::Item;`
`fn take_while<P>(self, predicate: P) -> TakeWhile<Self, P> where
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>`[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>`[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
F: FnMut(&mut St, <I as Iterator>::Item) -> Option<B>,
I: Iterator, type Item = B;`
`fn scan<St, B, F>(self, initial_state: St, f: F) -> Scan<Self, St, F> where
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, U, F> Iterator for FlatMap<I, U, F> where
F: FnMut(<I as Iterator>::Item) -> U,
I: Iterator,
U: IntoIterator, type Item = <U as IntoIterator>::Item;`
`fn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F> where
F: FnMut(Self::Item) -> U,
U: IntoIterator,` [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 as Iterator>::Item: IntoIterator,
<<I as Iterator>::Item as IntoIterator>::IntoIter == U,
<<I as Iterator>::Item as IntoIterator>::Item == <U as Iterator>::Item, type Item = <U as Iterator>::Item;`
`fn flatten(self) -> Flatten<Self> where
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: FusedIterator, impl<I> Iterator for Fuse<I> where
I: Iterator, type Item = <I as Iterator>::Item;`
`fn fuse(self) -> Fuse<Self>`[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, F> Iterator for Inspect<I, F> where
F: FnMut(&<I as Iterator>::Item),
I: Iterator, type Item = <I as Iterator>::Item;`
`fn inspect<F>(self, f: F) -> Inspect<Self, F> where
F: FnMut(&Self::Item),` [src]

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

####
ⓘImportant traits for &'_ mut I

### Important traits for &'_ mut I

`impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized, type Item = <I as Iterator>::Item;impl<'a, R: Read + ?Sized> Read for &'a mut Rimpl<'a, W: Write + ?Sized> Write for &'a mut W`
`fn by_ref(&mut self) -> &mut Self`[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>(self) -> B where
B: FromIterator<Self::Item>,` [src]

Transforms an iterator into a collection. Read more

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

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

#### `fn try_fold<B, F, R>(&mut self, init: B, f: F) -> R where
F: FnMut(B, Self::Item) -> R,
R: Try<Ok = B>,`
1.27.0
[src]

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

#### `fn try_for_each<F, R>(&mut self, f: F) -> R where
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 fold<B, F>(self, init: B, f: F) -> B where
F: FnMut(B, Self::Item) -> B,` [src]

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

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

Tests if any element of the iterator matches a predicate. 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 find_map<B, F>(&mut self, f: F) -> Option<B> where
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
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: ExactSizeIterator + DoubleEndedIterator,` [src]

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

#### `fn max_by_key<B, F>(self, f: F) -> Option<Self::Item> where
B: Ord,
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
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, F>(self, f: F) -> Option<Self::Item> where
B: Ord,
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
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: 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: 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> Iterator for Copied<I> where
I: Iterator<Item = &'a T>,
T: 'a + Copy, type Item = T;`
`fn copied<'a, T>(self) -> Copied<Self> where
Self: Iterator<Item = &'a T>,
T: 'a + 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> Iterator for Cloned<I> where
I: Iterator<Item = &'a T>,
T: 'a + Clone, type Item = T;`
`fn cloned<'a, T>(self) -> Cloned<Self> where
Self: Iterator<Item = &'a T>,
T: 'a + 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: Clone,` [src]

Repeats an iterator endlessly. Read more

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

Sums the elements of an iterator. Read more

#### `fn product<P>(self) -> P where
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,`
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 as IntoIterator>::Item>,`
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 as IntoIterator>::Item>,`
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 as IntoIterator>::Item>,`
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 as IntoIterator>::Item>,`
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 as IntoIterator>::Item>,`
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 as IntoIterator>::Item>,`
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 as IntoIterator>::Item>,`
1.5.0
[src]

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

### `impl<'_, T> RangeBounds<T> for Range<&'_ T>`
1.28.0
[src]

#### `fn start_bound(&self) -> Bound<&T>`[src]

Start index bound. Read more

#### `fn end_bound(&self) -> Bound<&T>`[src]

End index bound. Read more

#### `fn contains<U>(&self, item: &U) -> bool where
T: PartialOrd<U>,
U: PartialOrd<T> + ?Sized,` [src]

🔬 This is a nightly-only experimental API. (`range_contains` #32311)

recently added as per RFC

Returns `true` if `item` is contained in the range. Read more

### `impl<T> RangeBounds<T> for Range<T>`
1.28.0
[src]

#### `fn start_bound(&self) -> Bound<&T>`[src]

Start index bound. Read more

#### `fn end_bound(&self) -> Bound<&T>`[src]

End index bound. Read more

#### `fn contains<U>(&self, item: &U) -> bool where
T: PartialOrd<U>,
U: PartialOrd<T> + ?Sized,` [src]

🔬 This is a nightly-only experimental API. (`range_contains` #32311)

recently added as per RFC

Returns `true` if `item` is contained in the range. Read more

### `impl<Idx> Debug for Range<Idx> where
Idx: Debug,` [src]

#### `fn fmt(&self, fmt: &mut Formatter) -> Result<(), Error>`[src]

Formats the value using the given formatter. Read more

### `impl TrustedLen for Range<isize>`[src]

### `impl TrustedLen for Range<u8>`[src]

### `impl TrustedLen for Range<i16>`[src]

### `impl TrustedLen for Range<i64>`[src]

### `impl TrustedLen for Range<u32>`[src]

### `impl TrustedLen for Range<usize>`[src]

### `impl TrustedLen for Range<i8>`[src]

### `impl TrustedLen for Range<i32>`[src]

### `impl TrustedLen for Range<u16>`[src]

### `impl TrustedLen for Range<u64>`[src]

### `impl<Idx> Hash for Range<Idx> where
Idx: Hash,` [src]

#### `fn hash<__HIdx>(&self, state: &mut __HIdx) where
__HIdx: Hasher,` [src]

Feeds this value into the given [`Hasher`]. Read more

#### `fn hash_slice<H>(data: &[Self], state: &mut H) where
H: Hasher,`
1.3.0
[src]

Feeds a slice of this type into the given [`Hasher`]. Read more

### `impl ExactSizeIterator for Range<i32>`[src]

#### `fn len(&self) -> usize`[src]

Returns the exact number of times the iterator will iterate. Read more

#### `fn is_empty(&self) -> bool`[src]

🔬 This is a nightly-only experimental API. (`exact_size_is_empty` #35428)

Returns whether the iterator is empty. Read more

### `impl ExactSizeIterator for Range<u32>`[src]

#### `fn len(&self) -> usize`[src]

Returns the exact number of times the iterator will iterate. Read more

#### `fn is_empty(&self) -> bool`[src]

🔬 This is a nightly-only experimental API. (`exact_size_is_empty` #35428)

Returns whether the iterator is empty. Read more

### `impl ExactSizeIterator for Range<i16>`[src]

#### `fn len(&self) -> usize`[src]

Returns the exact number of times the iterator will iterate. Read more

#### `fn is_empty(&self) -> bool`[src]

🔬 This is a nightly-only experimental API. (`exact_size_is_empty` #35428)

Returns whether the iterator is empty. Read more

### `impl ExactSizeIterator for Range<u8>`[src]

#### `fn len(&self) -> usize`[src]

Returns the exact number of times the iterator will iterate. Read more

#### `fn is_empty(&self) -> bool`[src]

🔬 This is a nightly-only experimental API. (`exact_size_is_empty` #35428)

Returns whether the iterator is empty. Read more

### `impl ExactSizeIterator for Range<usize>`[src]

#### `fn len(&self) -> usize`[src]

Returns the exact number of times the iterator will iterate. Read more

#### `fn is_empty(&self) -> bool`[src]

🔬 This is a nightly-only experimental API. (`exact_size_is_empty` #35428)

Returns whether the iterator is empty. Read more

### `impl ExactSizeIterator for Range<u16>`[src]

#### `fn len(&self) -> usize`[src]

Returns the exact number of times the iterator will iterate. Read more

#### `fn is_empty(&self) -> bool`[src]

🔬 This is a nightly-only experimental API. (`exact_size_is_empty` #35428)

Returns whether the iterator is empty. Read more

### `impl ExactSizeIterator for Range<i8>`[src]

#### `fn len(&self) -> usize`[src]

Returns the exact number of times the iterator will iterate. Read more

#### `fn is_empty(&self) -> bool`[src]

🔬 This is a nightly-only experimental API. (`exact_size_is_empty` #35428)

Returns whether the iterator is empty. Read more

### `impl ExactSizeIterator for Range<isize>`[src]

#### `fn len(&self) -> usize`[src]

Returns the exact number of times the iterator will iterate. Read more

#### `fn is_empty(&self) -> bool`[src]

🔬 This is a nightly-only experimental API. (`exact_size_is_empty` #35428)

Returns whether the iterator is empty. Read more

### `impl<Idx> Clone for Range<Idx> where
Idx: Clone,` [src]

####
ⓘImportant traits for Range<A>

### Important traits for Range<A>

`impl<A> Iterator for Range<A> where
A: Step, type Item = A;`
`fn clone(&self) -> Range<Idx>`[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> DoubleEndedIterator for Range<A> where
A: Step,` [src]

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

Removes and returns an element from the end of the iterator. 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 try_rfold<B, F, R>(&mut self, init: B, f: F) -> R where
F: FnMut(B, Self::Item) -> R,
R: Try<Ok = B>,`
1.27.0
[src]

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

#### `fn rfold<B, F>(self, accum: B, f: F) -> B where
F: FnMut(B, Self::Item) -> B,`
1.27.0
[src]

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

#### `fn rfind<P>(&mut self, predicate: P) -> Option<Self::Item> where
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 IndexMut<Range<usize>> for str`
1.3.0
[src]

Implements mutable substring slicing with syntax `&mut self[begin .. end]`.

Returns a mutable slice of the given string from the byte range [`begin`..`end`).

This operation is `O(1)`.

# Panics

Panics if `begin` or `end` does not point to the starting byte offset of a character (as defined by `is_char_boundary`). Requires that `begin <= end` and `end <= len` where `len` is the length of the string.

#### `fn index_mut(&mut self, index: Range<usize>) -> &mut str`[src]

Performs the mutable indexing (`container[index]`) operation.

### `impl Index<Range<usize>> for str`[src]

Implements substring slicing with syntax `&self[begin .. end]`.

Returns a slice of the given string from the byte range [`begin`..`end`).

This operation is `O(1)`.

# Panics

Panics if `begin` or `end` does not point to the starting byte offset of a character (as defined by `is_char_boundary`). Requires that `begin <= end` and `end <= len` where `len` is the length of the string.

# Examples

    let s = "Löwe 老虎 Léopard";
    assert_eq!(&s[0 .. 1], "L");

    assert_eq!(&s[1 .. 9], "öwe 老");

    // these will panic:
    // byte 2 lies within `ö`:
    // &s[2 ..3];

    // byte 8 lies within `老`
    // &s[1 .. 8];

    // byte 100 is outside the string
    // &s[3 .. 100];Run

#### `type Output = str`

The returned type after indexing.

#### `fn index(&self, index: Range<usize>) -> &str`[src]

Performs the indexing (`container[index]`) operation.

### `impl<Idx> Eq for Range<Idx> where
Idx: Eq,` [src]

### `impl<Idx> PartialEq<Range<Idx>> for Range<Idx> where
Idx: PartialEq<Idx>,` [src]

#### `fn eq(&self, other: &Range<Idx>) -> bool`[src]

This method tests for `self` and `other` values to be equal, and is used by `==`. Read more

#### `fn ne(&self, other: &Range<Idx>) -> bool`[src]

This method tests for `!=`.

### `impl<A> FusedIterator for Range<A> where
A: Step,`
1.26.0
[src]

### `impl SliceIndex<str> for Range<usize>`
1.20.0
[src]

#### `type Output = str`

The output type returned by methods.

#### `fn get(self, slice: &str) -> Option<&<Range<usize> as SliceIndex<str>>::Output>`[src]

🔬 This is a nightly-only experimental API. (`slice_index_methods` #0)

Returns a shared reference to the output at this location, if in bounds. Read more

#### `fn get_mut(
self,
slice: &mut str
) -> Option<&mut <Range<usize> as SliceIndex<str>>::Output>`[src]

🔬 This is a nightly-only experimental API. (`slice_index_methods` #0)

Returns a mutable reference to the output at this location, if in bounds. Read more

####
ⓘImportant traits for Range<A>

### Important traits for Range<A>

`impl<A> Iterator for Range<A> where
A: Step, type Item = A;`
`unsafe fn get_unchecked(
self,
slice: &str
) -> &<Range<usize> as SliceIndex<str>>::Output`[src]

🔬 This is a nightly-only experimental API. (`slice_index_methods` #0)

Returns a shared reference to the output at this location, without performing any bounds checking. Read more

####
ⓘImportant traits for Range<A>

### Important traits for Range<A>

`impl<A> Iterator for Range<A> where
A: Step, type Item = A;`
`unsafe fn get_unchecked_mut(
self,
slice: &mut str
) -> &mut <Range<usize> as SliceIndex<str>>::Output`[src]

🔬 This is a nightly-only experimental API. (`slice_index_methods` #0)

Returns a mutable reference to the output at this location, without performing any bounds checking. Read more

####
ⓘImportant traits for Range<A>

### Important traits for Range<A>

`impl<A> Iterator for Range<A> where
A: Step, type Item = A;`
`fn index(self, slice: &str) -> &<Range<usize> as SliceIndex<str>>::Output`[src]

🔬 This is a nightly-only experimental API. (`slice_index_methods` #0)

Returns a shared reference to the output at this location, panicking if out of bounds. Read more

####
ⓘImportant traits for Range<A>

### Important traits for Range<A>

`impl<A> Iterator for Range<A> where
A: Step, type Item = A;`
`fn index_mut(
self,
slice: &mut str
) -> &mut <Range<usize> as SliceIndex<str>>::Output`[src]

🔬 This is a nightly-only experimental API. (`slice_index_methods` #0)

Returns a mutable reference to the output at this location, panicking if out of bounds. Read more

### `impl<T> SliceIndex<[T]> for Range<usize>`
1.15.0
[src]

#### `type Output = [T]`

The output type returned by methods.

#### `fn get(self, slice: &[T]) -> Option<&[T]>`[src]

🔬 This is a nightly-only experimental API. (`slice_index_methods` #0)

Returns a shared reference to the output at this location, if in bounds. Read more

#### `fn get_mut(self, slice: &mut [T]) -> Option<&mut [T]>`[src]

🔬 This is a nightly-only experimental API. (`slice_index_methods` #0)

Returns a mutable reference to the output at this location, if in bounds. Read more

####
ⓘImportant traits for &'a [u8]

### Important traits for &'a [u8]

`impl<'a> Read for &'a [u8]impl<'a> Write for &'a mut [u8]`
`unsafe fn get_unchecked(self, slice: &[T]) -> &[T]`[src]

🔬 This is a nightly-only experimental API. (`slice_index_methods` #0)

Returns a shared reference to the output at this location, without performing any bounds checking. Read more

####
ⓘImportant traits for &'a [u8]

### Important traits for &'a [u8]

`impl<'a> Read for &'a [u8]impl<'a> Write for &'a mut [u8]`
`unsafe fn get_unchecked_mut(self, slice: &mut [T]) -> &mut [T]`[src]

🔬 This is a nightly-only experimental API. (`slice_index_methods` #0)

Returns a mutable reference to the output at this location, without performing any bounds checking. Read more

####
ⓘImportant traits for &'a [u8]

### Important traits for &'a [u8]

`impl<'a> Read for &'a [u8]impl<'a> Write for &'a mut [u8]`
`fn index(self, slice: &[T]) -> &[T]`[src]

🔬 This is a nightly-only experimental API. (`slice_index_methods` #0)

Returns a shared reference to the output at this location, panicking if out of bounds. Read more

####
ⓘImportant traits for &'a [u8]

### Important traits for &'a [u8]

`impl<'a> Read for &'a [u8]impl<'a> Write for &'a mut [u8]`
`fn index_mut(self, slice: &mut [T]) -> &mut [T]`[src]

🔬 This is a nightly-only experimental API. (`slice_index_methods` #0)

Returns a mutable reference to the output at this location, panicking if out of bounds. Read more

### `impl Index<Range<usize>> for String`[src]

#### `type Output = str`

The returned type after indexing.

#### `fn index(&self, index: Range<usize>) -> &str`[src]

Performs the indexing (`container[index]`) operation.

### `impl IndexMut<Range<usize>> for String`
1.3.0
[src]

#### `fn index_mut(&mut self, index: Range<usize>) -> &mut str`[src]

Performs the mutable indexing (`container[index]`) operation.

## Auto Trait Implementations

### `impl<Idx> Send for Range<Idx> where
Idx: Send,`

### `impl<Idx> Sync for Range<Idx> where
Idx: Sync,`

## Blanket Implementations

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

#### `fn from(t: T) -> T`[src]

Performs the conversion.

### `impl<I> IntoIterator for I where
I: Iterator,` [src]

#### `type Item = <I as Iterator>::Item`

The type of the elements being iterated over.

#### `type IntoIter = I`

Which kind of iterator are we turning this into?

#### `fn into_iter(self) -> I`[src]

Creates an iterator from a value. Read more

### `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(value: U) -> Result<T, <T as TryFrom<U>>::Error>`[src]

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

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

#### `fn into(self) -> U`[src]

Performs the conversion.

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

####
ⓘImportant traits for &'_ mut I

### Important traits for &'_ mut I

`impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized, type Item = <I as Iterator>::Item;impl<'a, R: Read + ?Sized> Read for &'a mut Rimpl<'a, W: Write + ?Sized> Write for &'a mut W`
`fn borrow(&self) -> &T`[src]

Immutably borrows from an owned value. Read more

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

####
ⓘImportant traits for &'_ mut I

### Important traits for &'_ mut I

`impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized, type Item = <I as Iterator>::Item;impl<'a, R: Read + ?Sized> Read for &'a mut Rimpl<'a, W: Write + ?Sized> Write for &'a mut W`
`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

### `impl<T> ToOwned for T where
T: Clone,` [src]

#### `type Owned = T`

#### `fn to_owned(&self) -> T`[src]

Creates owned data from borrowed data, usually by cloning. Read more

#### `fn clone_into(&self, target: &mut T)`[src]

🔬 This is a nightly-only experimental API. (`toowned_clone_into` #41263)

recently added

Uses borrowed data to replace owned data, usually by cloning. Read more

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