Struct std::ops::RangeFrom

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  ]);

Fields

start: Idx

The lower bound of the range (inclusive).

Methods

impl<Idx> RangeFrom<Idx> where     Idx: PartialOrd<Idx>,

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

🔬 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..).contains(&2));
assert!( (3..).contains(&3));
assert!( (3..).contains(&1_000_000_000));

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

Trait Implementations

impl<Idx> Debug for RangeFrom<Idx> where     Idx: Debug,

fn fmt(&self, fmt: &mut Formatter) -> Result<(), Error>

Formats the value using the given formatter.

impl<T> RangeBounds<T> for RangeFrom<T>

fn start_bound(&self) -> Bound<&T>

Start index bound.

fn end_bound(&self) -> Bound<&T>

End index bound.

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

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

recently added as per RFC

Returns true if item is contained in the range.

impl<'a, T> RangeBounds<T> for RangeFrom<&'a T>

fn start_bound(&self) -> Bound<&T>

Start index bound.

fn end_bound(&self) -> Bound<&T>

End index bound.

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

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

recently added as per RFC

Returns true if item is contained in the range.

impl<A> TrustedLen for RangeFrom<A> where     A: Step,

impl IndexMut<RangeFrom<usize>> for str

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

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

impl Index<RangeFrom<usize>> for str

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

Performs the indexing (container[index]) operation.

impl<Idx> Clone for RangeFrom<Idx> where     Idx: Clone,

Important traits for RangeFrom<A>

impl<A> Iterator for RangeFrom<A> where
    A: Step,  type Item = A;

fn clone(&self) -> RangeFrom<Idx>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<A> Iterator for RangeFrom<A> where     A: Step,

type Item = A

The type of the elements being iterated over.

fn next(&mut self) -> Option<A>

Advances the iterator and returns the next value.

fn size_hint(&self) -> (usize, Option<usize>)

Returns the bounds on the remaining length of the iterator.

fn nth(&mut self, n: usize) -> Option<A>

Returns the nth element of the iterator.

fn count(self) -> usize

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

fn last(self) -> Option<Self::Item>

Consumes the iterator, returning the last element.

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>

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

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>,

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

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,

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

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,

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

fn for_each<F>(self, f: F) where     F: FnMut(Self::Item),

Calls a closure on each element of an iterator.

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,

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

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>,

Creates an iterator that both filters and maps.

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>

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

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>

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

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,

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

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,

Creates an iterator that yields elements based on a predicate.

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>

Creates an iterator that skips the first n elements.

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>

Creates an iterator that yields its first n elements.

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>,

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

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,

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

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,

🔬 This is a nightly-only experimental API. (iterator_flatten #48213)

Creates an iterator that flattens nested structure.

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>

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

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),

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

Important traits for &'a mut I

impl<'a, I> Iterator for &'a 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

Borrows an iterator, rather than consuming it.

#[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>,

Transforms an iterator into a collection.

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

Consumes an iterator, creating two collections from it.

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

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

fn try_for_each<F, R>(&mut self, f: F) -> R where     F: FnMut(Self::Item) -> R,     R: Try<Ok = ()>,

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

fn fold<B, F>(self, init: B, f: F) -> B where     F: FnMut(B, Self::Item) -> B,

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

fn all<F>(&mut self, f: F) -> bool where     F: FnMut(Self::Item) -> bool,

Tests if every element of the iterator matches a predicate.

fn any<F>(&mut self, f: F) -> bool where     F: FnMut(Self::Item) -> bool,

Tests if any element of the iterator matches a predicate.

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

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

fn find_map<B, F>(&mut self, f: F) -> Option<B> where     F: FnMut(Self::Item) -> Option<B>,

🔬 This is a nightly-only experimental API. (iterator_find_map #49602)

unstable new API

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

fn position<P>(&mut self, predicate: P) -> Option<usize> where     P: FnMut(Self::Item) -> bool,

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

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

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

fn max(self) -> Option<Self::Item> where     Self::Item: Ord,

Returns the maximum element of an iterator.

fn min(self) -> Option<Self::Item> where     Self::Item: Ord,

Returns the minimum element of an iterator.

fn max_by_key<B, F>(self, f: F) -> Option<Self::Item> where     B: Ord,     F: FnMut(&Self::Item) -> B,

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

fn max_by<F>(self, compare: F) -> Option<Self::Item> where     F: FnMut(&Self::Item, &Self::Item) -> Ordering,

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

fn min_by_key<B, F>(self, f: F) -> Option<Self::Item> where     B: Ord,     F: FnMut(&Self::Item) -> B,

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

fn min_by<F>(self, compare: F) -> Option<Self::Item> where     F: FnMut(&Self::Item, &Self::Item) -> Ordering,

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

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,

Reverses an iterator's direction.

fn unzip<A, B, FromA, FromB>(self) -> (FromA, FromB) where     FromA: Default + Extend<A>,     FromB: Default + Extend<B>,     Self: Iterator<Item = (A, B)>,

Converts an iterator of pairs into a pair of containers.

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,

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

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,

Repeats an iterator endlessly.

fn sum<S>(self) -> S where     S: Sum<Self::Item>,

Sums the elements of an iterator.

fn product<P>(self) -> P where     P: Product<Self::Item>,

Iterates over the entire iterator, multiplying all the elements

fn cmp<I>(self, other: I) -> Ordering where     I: IntoIterator<Item = Self::Item>,     Self::Item: Ord,

Lexicographically compares the elements of this Iterator with those of another.

fn partial_cmp<I>(self, other: I) -> Option<Ordering> where     I: IntoIterator,     Self::Item: PartialOrd<<I as IntoIterator>::Item>,

Lexicographically compares the elements of this Iterator with those of another.

fn eq<I>(self, other: I) -> bool where     I: IntoIterator,     Self::Item: PartialEq<<I as IntoIterator>::Item>,

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

fn ne<I>(self, other: I) -> bool where     I: IntoIterator,     Self::Item: PartialEq<<I as IntoIterator>::Item>,

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

fn lt<I>(self, other: I) -> bool where     I: IntoIterator,     Self::Item: PartialOrd<<I as IntoIterator>::Item>,

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

fn le<I>(self, other: I) -> bool where     I: IntoIterator,     Self::Item: PartialOrd<<I as IntoIterator>::Item>,

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

fn gt<I>(self, other: I) -> bool where     I: IntoIterator,     Self::Item: PartialOrd<<I as IntoIterator>::Item>,

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

fn ge<I>(self, other: I) -> bool where     I: IntoIterator,     Self::Item: PartialOrd<<I as IntoIterator>::Item>,

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

impl<Idx> Eq for RangeFrom<Idx> where     Idx: Eq,

impl<Idx> PartialEq<RangeFrom<Idx>> for RangeFrom<Idx> where     Idx: PartialEq<Idx>,

fn eq(&self, other: &RangeFrom<Idx>) -> bool

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

fn ne(&self, other: &RangeFrom<Idx>) -> bool

This method tests for !=.

impl<A> FusedIterator for RangeFrom<A> where     A: Step,

impl<T> SliceIndex<[T]> for RangeFrom<usize>

type Output = [T]

The output type returned by methods.

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

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

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

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

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

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

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]

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

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

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]

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

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

Important traits for &'a [u8]

impl<'a> Read for &'a [u8]impl<'a> Write for &'a mut [u8]

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

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

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

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]

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

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

impl SliceIndex<str> for RangeFrom<usize>

type Output = str

The output type returned by methods.

fn get(     self,     slice: &str ) -> Option<&<RangeFrom<usize> as SliceIndex<str>>::Output>

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

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

fn get_mut(     self,     slice: &mut str ) -> Option<&mut <RangeFrom<usize> as SliceIndex<str>>::Output>

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

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

Important traits for RangeFrom<A>

impl<A> Iterator for RangeFrom<A> where
    A: Step,  type Item = A;

unsafe fn get_unchecked(     self,     slice: &str ) -> &<RangeFrom<usize> as SliceIndex<str>>::Output

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

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

Important traits for RangeFrom<A>

impl<A> Iterator for RangeFrom<A> where
    A: Step,  type Item = A;

unsafe fn get_unchecked_mut(     self,     slice: &mut str ) -> &mut <RangeFrom<usize> as SliceIndex<str>>::Output

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

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

Important traits for RangeFrom<A>

impl<A> Iterator for RangeFrom<A> where
    A: Step,  type Item = A;

fn index(self, slice: &str) -> &<RangeFrom<usize> as SliceIndex<str>>::Output

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

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

Important traits for RangeFrom<A>

impl<A> Iterator for RangeFrom<A> where
    A: Step,  type Item = A;

fn index_mut(     self,     slice: &mut str ) -> &mut <RangeFrom<usize> as SliceIndex<str>>::Output

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

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

impl<Idx> Hash for RangeFrom<Idx> where     Idx: Hash,

fn hash<__HIdx>(&self, state: &mut __HIdx) where     __HIdx: Hasher,

Feeds this value into the given [Hasher].

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

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

impl Index<RangeFrom<usize>> for String

type Output = str

The returned type after indexing.

fn index(&self, index: RangeFrom<usize>) -> &str

Performs the indexing (container[index]) operation.

impl IndexMut<RangeFrom<usize>> for String

fn index_mut(&mut self, index: RangeFrom<usize>) -> &mut str

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