Struct indexmap::map::Keys[][src]

pub struct Keys<'a, K, V> { /* fields omitted */ }
Expand description

An iterator over the keys of a IndexMap.

This struct is created by the keys method on IndexMap. See its documentation for more.

Trait Implementations

impl<K, V> Clone for Keys<'_, K, V>[src]

fn clone(&self) -> Self[src]

Returns a copy of the value. Read more

fn clone_from(&mut self, source: &Self)1.0.0[src]

Performs copy-assignment from source. Read more

impl<K: Debug, V> Debug for Keys<'_, K, V>[src]

fn fmt(&self, f: &mut Formatter<'_>) -> Result[src]

Formats the value using the given formatter. Read more

impl<K, V> DoubleEndedIterator for Keys<'_, K, V>[src]

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

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

fn advance_back_by(&mut self, n: usize) -> Result<(), usize>[src]

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

recently added

Advances the iterator from the back by n elements. Read more

fn nth_back(&mut self, n: usize) -> Option<Self::Item>1.37.0[src]

Returns the nth 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 Iterator::try_fold(): it takes elements starting from the back of the iterator. Read more

fn rfold<B, F>(self, init: 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<K, V> ExactSizeIterator for Keys<'_, K, V>[src]

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

Returns the exact length of the iterator. Read more

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

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

Returns true if the iterator is empty. Read more

impl<'a, K, V> Iterator for Keys<'a, K, V>[src]

type Item = &'a K

The type of the elements being iterated over.

fn next(&mut self) -> Option<Self::Item>[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 count(self) -> usize[src]

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

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

Returns the nth element of the iterator. Read more

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

Consumes the iterator, returning the last element. Read more

fn collect<C>(self) -> C where
    C: FromIterator<Self::Item>, 
[src]

Transforms an iterator into a collection. Read more

fn advance_by(&mut self, n: usize) -> Result<(), usize>[src]

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

recently added

Advances the iterator by n elements. Read more

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

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

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

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

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

fn intersperse(self, separator: Self::Item) -> Intersperse<Self> where
    Self::Item: Clone
[src]

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

recently added

Creates a new iterator which places a copy of separator between adjacent items of the original iterator. Read more

fn intersperse_with<G>(self, separator: G) -> IntersperseWith<Self, G> where
    G: FnMut() -> Self::Item
[src]

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

recently added

Creates a new iterator which places an item generated by separator between adjacent items of the original iterator. Read more

fn map<B, F>(self, f: F) -> Map<Self, F> where
    F: FnMut(Self::Item) -> B, 
1.0.0[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

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

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

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

Creates an iterator that both filters and maps. Read more

fn enumerate(self) -> Enumerate<Self>1.0.0[src]

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

fn peekable(self) -> Peekable<Self>1.0.0[src]

Creates an iterator which can use the peek and peek_mut methods to look at the next element of the iterator without consuming it. See their documentation for more information. Read more

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

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

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

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

fn map_while<B, P>(self, predicate: P) -> MapWhile<Self, P> where
    P: FnMut(Self::Item) -> Option<B>, 
[src]

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

recently added

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

fn skip(self, n: usize) -> Skip<Self>1.0.0[src]

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

fn take(self, n: usize) -> Take<Self>1.0.0[src]

Creates an iterator that yields the first n elements, or fewer if the underlying iterator ends sooner. Read more

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

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

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

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

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

Creates an iterator that flattens nested structure. Read more

fn fuse(self) -> Fuse<Self>1.0.0[src]

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

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

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

fn by_ref(&mut self) -> &mut Self1.0.0[src]

Borrows an iterator, rather than consuming it. Read more

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

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

fn partition_in_place<'a, T, P>(self, predicate: P) -> usize where
    Self: DoubleEndedIterator<Item = &'a mut T>,
    T: 'a,
    P: FnMut(&T) -> bool
[src]

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

new API

Reorders the elements of this iterator in-place according to the given predicate, such that all those that return true precede all those that return false. Returns the number of true elements found. Read more

fn is_partitioned<P>(self, predicate: P) -> bool where
    P: FnMut(Self::Item) -> bool
[src]

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

new API

Checks if the elements of this iterator are partitioned according to the given predicate, such that all those that return true precede all those that return false. 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, 
1.0.0[src]

Folds every element into an accumulator by applying an operation, returning the final result. Read more

fn reduce<F>(self, f: F) -> Option<Self::Item> where
    F: FnMut(Self::Item, Self::Item) -> Self::Item
1.51.0[src]

Reduces the elements to a single one, by repeatedly applying a reducing operation. Read more

fn all<F>(&mut self, f: F) -> bool where
    F: FnMut(Self::Item) -> bool
1.0.0[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
1.0.0[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
1.0.0[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 try_find<F, R>(
    &mut self,
    f: F
) -> Result<Option<Self::Item>, <R as Try>::Error> where
    F: FnMut(&Self::Item) -> R,
    R: Try<Ok = bool>, 
[src]

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

new API

Applies function to the elements of iterator and returns the first true result or the first error. Read more

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

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

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

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

fn max(self) -> Option<Self::Item> where
    Self::Item: Ord
1.0.0[src]

Returns the maximum element of an iterator. Read more

fn min(self) -> Option<Self::Item> where
    Self::Item: Ord
1.0.0[src]

Returns the minimum element of an iterator. Read more

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

fn rev(self) -> Rev<Self> where
    Self: DoubleEndedIterator
1.0.0[src]

Reverses an iterator’s direction. Read more

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

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

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

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

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

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

fn cycle(self) -> Cycle<Self> where
    Self: Clone
1.0.0[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 cmp_by<I, F>(self, other: I, cmp: F) -> Ordering where
    F: FnMut(Self::Item, <I as IntoIterator>::Item) -> Ordering,
    I: IntoIterator
[src]

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

Lexicographically compares the elements of this Iterator with those of another with respect to the specified comparison function. 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 partial_cmp_by<I, F>(self, other: I, partial_cmp: F) -> Option<Ordering> where
    F: FnMut(Self::Item, <I as IntoIterator>::Item) -> Option<Ordering>,
    I: IntoIterator
[src]

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

Lexicographically compares the elements of this Iterator with those of another with respect to the specified comparison function. 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 eq_by<I, F>(self, other: I, eq: F) -> bool where
    F: FnMut(Self::Item, <I as IntoIterator>::Item) -> bool,
    I: IntoIterator
[src]

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

Determines if the elements of this Iterator are equal to those of another with respect to the specified equality function. 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

fn is_sorted(self) -> bool where
    Self::Item: PartialOrd<Self::Item>, 
[src]

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

new API

Checks if the elements of this iterator are sorted. Read more

fn is_sorted_by<F>(self, compare: F) -> bool where
    F: FnMut(&Self::Item, &Self::Item) -> Option<Ordering>, 
[src]

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

new API

Checks if the elements of this iterator are sorted using the given comparator function. Read more

fn is_sorted_by_key<F, K>(self, f: F) -> bool where
    K: PartialOrd<K>,
    F: FnMut(Self::Item) -> K, 
[src]

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

new API

Checks if the elements of this iterator are sorted using the given key extraction function. Read more

Auto Trait Implementations

impl<'a, K, V> RefUnwindSafe for Keys<'a, K, V> where
    K: RefUnwindSafe,
    V: RefUnwindSafe

impl<'a, K, V> Send for Keys<'a, K, V> where
    K: Sync,
    V: Sync

impl<'a, K, V> Sync for Keys<'a, K, V> where
    K: Sync,
    V: Sync

impl<'a, K, V> Unpin for Keys<'a, K, V>

impl<'a, K, V> UnwindSafe for Keys<'a, K, V> where
    K: RefUnwindSafe,
    V: RefUnwindSafe

Blanket Implementations

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

pub fn type_id(&self) -> TypeId[src]

Gets the TypeId of self. Read more

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

pub fn borrow(&self) -> &T[src]

Immutably borrows from an owned value. Read more

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

pub fn borrow_mut(&mut self) -> &mut T[src]

Mutably borrows from an owned value. Read more

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

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

Performs the conversion.

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

pub fn into(self) -> U[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?

pub fn into_iter(self) -> I[src]

Creates an iterator from a value. Read more

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

type Owned = T

The resulting type after obtaining ownership.

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

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

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

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

recently added

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

impl<T, U> TryFrom<U> for T where
    U: Into<T>, 
[src]

type Error = Infallible

The type returned in the event of a conversion error.

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

Performs the conversion.

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

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

The type returned in the event of a conversion error.

pub fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>[src]

Performs the conversion.