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

# Struct core::ops::RangeFrom 1.0.0 [−] [src]

    pub struct RangeFrom<Idx> {
        pub start: Idx,
    }

A range only bounded inclusively below (`start..`).

The `RangeFrom` `start..` contains all values with `x >= start`.

Note: Currently, no overflow checking is done for the `Iterator` implementation; if you use an integer range and the integer overflows, it might panic in debug mode or create an endless loop in release mode. This overflow behavior might change in the future.

# Examples

    assert_eq!((2..), std::ops::RangeFrom { start: 2 });
    assert_eq!(2 + 3 + 4, (2..).take(3).sum());

    let arr = [0, 1, 2, 3];
    assert_eq!(arr[ .. ], [0,1,2,3]);
    assert_eq!(arr[ ..3], [0,1,2  ]);
    assert_eq!(arr[1.. ], [  1,2,3]);  // RangeFrom
    assert_eq!(arr[1..3], [  1,2  ]);Run

## Fields

`start: Idx`

The lower bound of the range (inclusive).

## Methods

### `impl<Idx: PartialOrd<Idx>> RangeFrom<Idx>`
[src]

#### `pub fn contains(&self, item: Idx) -> bool`
[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)]

    assert!(!(3..).contains(2));
    assert!( (3..).contains(3));
    assert!( (3..).contains(1_000_000_000));Run

## Trait Implementations

### `impl<Idx: Clone> Clone for RangeFrom<Idx>`
[src]

####
ⓘImportant traits for RangeFrom<A>

### Important traits for RangeFrom<A>

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

#### `fn eq(&self, __arg_0: &RangeFrom<Idx>) -> bool`
[src]

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

#### `fn ne(&self, __arg_0: &RangeFrom<Idx>) -> bool`
[src]

This method tests for `!=`.

### `impl<Idx: Eq> Eq for RangeFrom<Idx>`
[src]

### `impl<Idx: Hash> Hash for RangeFrom<Idx>`
[src]

#### `fn hash<__HIdx: Hasher>(&self, __arg_0: &mut __HIdx)`
[src]

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

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

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

### `impl<Idx: Debug> Debug for RangeFrom<Idx>`
[src]

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

Formats the value using the given formatter. Read more

### `impl<A: Step> Iterator for RangeFrom<A>`
[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 count(self) -> usize where
Self: Sized,`
[src]

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

#### `fn last(self) -> Option<Self::Item> where
Self: Sized,`
[src]

Consumes the iterator, returning the last element. 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,`
[src]

🔬 This is a nightly-only experimental API. (`iterator_step_by` #27741)

unstable replacement of Range::step_by

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 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

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

🔬 This is a nightly-only experimental API. (`iterator_try_fold` #45594)

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

#### `fn fold<B, F>(self, init: B, f: F) -> B where
Self: Sized,
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
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<P>(&mut self, predicate: P) -> Option<Self::Item> where
Self: Sized,
P: FnMut(&Self::Item) -> bool,`
[src]

Searches for an element of an iterator that satisfies a predicate. 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 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: Step> FusedIterator for RangeFrom<A>`
[src]

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

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

🔬 This is a nightly-only experimental API. (`slice_get_slice` #35729)

The output type returned by methods.

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

🔬 This is a nightly-only experimental API. (`slice_get_slice` #35729)

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_get_slice` #35729)

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

#### `unsafe fn get_unchecked(self, slice: &[T]) -> &[T]`
[src]

🔬 This is a nightly-only experimental API. (`slice_get_slice` #35729)

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

#### `unsafe fn get_unchecked_mut(self, slice: &mut [T]) -> &mut [T]`
[src]

🔬 This is a nightly-only experimental API. (`slice_get_slice` #35729)

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

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

🔬 This is a nightly-only experimental API. (`slice_get_slice` #35729)

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

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

🔬 This is a nightly-only experimental API. (`slice_get_slice` #35729)

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

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

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

Returns a slice of the string from byte offset `begin` to the end of the string.

Equivalent to `&self[begin .. len]`.

#### `type Output = str`

The returned type after indexing.

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

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

### `impl IndexMut<RangeFrom<usize>> for str`
1.3.0
[src]

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

Returns a mutable slice of the string from byte offset `begin` to the end of the string.

Equivalent to `&mut self[begin .. len]`.

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

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

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

#### `type Output = str`

🔬 This is a nightly-only experimental API. (`slice_get_slice` #35729)

The output type returned by methods.

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

🔬 This is a nightly-only experimental API. (`slice_get_slice` #35729)

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

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

🔬 This is a nightly-only experimental API. (`slice_get_slice` #35729)

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

#### `unsafe fn get_unchecked(self, slice: &str) -> &Self::Output`
[src]

🔬 This is a nightly-only experimental API. (`slice_get_slice` #35729)

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

#### `unsafe fn get_unchecked_mut(self, slice: &mut str) -> &mut Self::Output`
[src]

🔬 This is a nightly-only experimental API. (`slice_get_slice` #35729)

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

#### `fn index(self, slice: &str) -> &Self::Output`
[src]

🔬 This is a nightly-only experimental API. (`slice_get_slice` #35729)

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

#### `fn index_mut(self, slice: &mut str) -> &mut Self::Output`
[src]

🔬 This is a nightly-only experimental API. (`slice_get_slice` #35729)

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

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