Trait std::iter::FusedIterator

pub trait FusedIterator: Iterator { }

🔬 This is a nightly-only experimental API. (fused #35602)

An iterator that always continues to yield None when exhausted.

Calling next on a fused iterator that has returned None once is guaranteed to return None again. This trait should be implemented by all iterators that behave this way because it allows for some significant optimizations.

Note: In general, you should not use FusedIterator in generic bounds if you need a fused iterator. Instead, you should just call Iterator::fuse on the iterator. If the iterator is already fused, the additional Fuse wrapper will be a no-op with no performance penalty.

Implementations on Foreign Types

impl<I> FusedIterator for Utf16Encoder<I> where
    I: FusedIterator<Item = char>, 

Implementors

• impl<'a> FusedIterator for SplitWhitespace<'a>
• impl FusedIterator for ToLowercase
• impl FusedIterator for ToUppercase
• impl<'a, P> FusedIterator for RMatchIndices<'a, P> where
    P: Pattern<'a>,
    <P as Pattern<'a>>::Searcher: ReverseSearcher<'a>, 
• impl<T> FusedIterator for Once<T>
• impl<'a, T, P> FusedIterator for std::slice::SplitN<'a, T, P> where
    P: FnMut(&T) -> bool, 
• impl<'a, T> FusedIterator for ChunksMut<'a, T>
• impl<I, P> FusedIterator for TakeWhile<I, P> where
    I: FusedIterator,
    P: FnMut(&<I as Iterator>::Item) -> bool, 
• impl<'a, T> FusedIterator for Chunks<'a, T>
• impl<I> FusedIterator for Enumerate<I> where
    I: FusedIterator, 
• impl<I> FusedIterator for Rev<I> where
    I: FusedIterator + DoubleEndedIterator, 
• impl<'a, P> FusedIterator for std::str::SplitN<'a, P> where
    P: Pattern<'a>, 
• impl<'a, P> FusedIterator for SplitTerminator<'a, P> where
    P: Pattern<'a>, 
• impl<'a, T> FusedIterator for std::result::IterMut<'a, T>
• impl<'a, T, P> FusedIterator for SplitNMut<'a, T, P> where
    P: FnMut(&T) -> bool, 
• impl<'a> FusedIterator for Lines<'a>
• impl<'a, T, P> FusedIterator for RSplitMut<'a, T, P> where
    P: FnMut(&T) -> bool, 
• impl<'a, T, P> FusedIterator for std::slice::Split<'a, T, P> where
    P: FnMut(&T) -> bool, 
• impl<A> FusedIterator for Repeat<A> where
    A: Clone, 
• impl<'a, P> FusedIterator for std::str::RSplitN<'a, P> where
    P: Pattern<'a>,
    <P as Pattern<'a>>::Searcher: ReverseSearcher<'a>, 
• impl<'a, P> FusedIterator for RMatches<'a, P> where
    P: Pattern<'a>,
    <P as Pattern<'a>>::Searcher: ReverseSearcher<'a>, 
• impl<A> FusedIterator for std::option::IntoIter<A>
• impl<I> FusedIterator for Skip<I> where
    I: FusedIterator, 
• impl<A> FusedIterator for RangeInclusive<A> where
    A: Step, 
• impl<'a> FusedIterator for Bytes<'a>
• impl<I, U, F> FusedIterator for FlatMap<I, U, F> where
    F: FnMut(<I as Iterator>::Item) -> U,
    I: FusedIterator,
    U: IntoIterator, 
• impl<'a, I, T> FusedIterator for Cloned<I> where
    I: FusedIterator<Item = &'a T>,
    T: 'a + Clone, 
• impl<B, I, F> FusedIterator for FilterMap<I, F> where
    F: FnMut(<I as Iterator>::Item) -> Option<B>,
    I: FusedIterator, 
• impl<A, B> FusedIterator for Zip<A, B> where
    A: FusedIterator,
    B: FusedIterator, 
• impl<B, I, F> FusedIterator for Map<I, F> where
    F: FnMut(<I as Iterator>::Item) -> B,
    I: FusedIterator, 
• impl<'a, T> FusedIterator for Windows<'a, T>
• impl<'a, T> FusedIterator for std::result::Iter<'a, T>
• impl<'a> FusedIterator for LinesAny<'a>
• impl<'a, A> FusedIterator for std::option::Iter<'a, A>
• impl<'a, P> FusedIterator for Matches<'a, P> where
    P: Pattern<'a>, 
• impl<I> FusedIterator for Take<I> where
    I: FusedIterator, 
• impl<T> FusedIterator for std::result::IntoIter<T>
• impl<'a, T> FusedIterator for std::slice::IterMut<'a, T>
• impl FusedIterator for std::char::EscapeDefault
• impl<'a, A> FusedIterator for std::option::IterMut<'a, A>
• impl FusedIterator for EscapeDebug
• impl<'a, T, P> FusedIterator for RSplitNMut<'a, T, P> where
    P: FnMut(&T) -> bool, 
• impl<'a, P> FusedIterator for RSplitTerminator<'a, P> where
    P: Pattern<'a>,
    <P as Pattern<'a>>::Searcher: ReverseSearcher<'a>, 
• impl<I, F> FusedIterator for Inspect<I, F> where
    F: FnMut(&<I as Iterator>::Item) -> (),
    I: FusedIterator, 
• impl<'a, T, P> FusedIterator for std::slice::RSplitN<'a, T, P> where
    P: FnMut(&T) -> bool, 
• impl<A, B> FusedIterator for Chain<A, B> where
    A: FusedIterator,
    B: FusedIterator<Item = <A as Iterator>::Item>, 
• impl<'a, I> FusedIterator for &'a mut I where
    I: FusedIterator + ?Sized, 
• impl FusedIterator for EscapeUnicode
• impl<I> FusedIterator for Cycle<I> where
    I: Clone + Iterator, 
• impl<'a, T, P> FusedIterator for std::slice::RSplit<'a, T, P> where
    P: FnMut(&T) -> bool, 
• impl<I> FusedIterator for Fuse<I> where
    I: Iterator, 
• impl<'a, T, P> FusedIterator for SplitMut<'a, T, P> where
    P: FnMut(&T) -> bool, 
• impl<'a, T> FusedIterator for std::slice::Iter<'a, T>
• impl<I> FusedIterator for Peekable<I> where
    I: FusedIterator, 
• impl<I, P> FusedIterator for Filter<I, P> where
    I: FusedIterator,
    P: FnMut(&<I as Iterator>::Item) -> bool, 
• impl<I, P> FusedIterator for SkipWhile<I, P> where
    I: FusedIterator,
    P: FnMut(&<I as Iterator>::Item) -> bool, 
• impl<'a, P> FusedIterator for std::str::Split<'a, P> where
    P: Pattern<'a>, 
• impl<'a, P> FusedIterator for std::str::RSplit<'a, P> where
    P: Pattern<'a>,
    <P as Pattern<'a>>::Searcher: ReverseSearcher<'a>, 
• impl<'a, P> FusedIterator for MatchIndices<'a, P> where
    P: Pattern<'a>, 
• impl<A> FusedIterator for std::ops::Range<A> where
    A: Step, 
• impl<I> FusedIterator for DecodeUtf8<I> where
    I: FusedIterator<Item = u8>, 
• impl<'a> FusedIterator for Chars<'a>
• impl<A> FusedIterator for RangeFrom<A> where
    A: Step, 
• impl<'a> FusedIterator for CharIndices<'a>
• impl<T> FusedIterator for Empty<T>
• impl<I> FusedIterator for Box<I> where
    I: FusedIterator + ?Sized, 
• impl<'a, T> FusedIterator for std::collections::btree_set::Union<'a, T> where
    T: Ord, 
• impl<'a, T> FusedIterator for std::collections::binary_heap::Iter<'a, T>
• impl<'a, K, V> FusedIterator for std::collections::btree_map::ValuesMut<'a, K, V>
• impl<'a, K, V> FusedIterator for std::collections::btree_map::Keys<'a, K, V>
• impl<T> FusedIterator for std::collections::vec_deque::IntoIter<T>
• impl<'a> FusedIterator for EncodeUtf16<'a>
• impl<'a, T> FusedIterator for std::collections::btree_set::Difference<'a, T> where
    T: Ord, 
• impl<'a> FusedIterator for std::string::Drain<'a>
• impl<'a, K, V> FusedIterator for std::collections::btree_map::IterMut<'a, K, V>
• impl<'a, T> FusedIterator for std::collections::binary_heap::Drain<'a, T> where
    T: 'a, 
• impl<'a, K, V> FusedIterator for std::collections::btree_map::Values<'a, K, V>
• impl<T> FusedIterator for std::collections::btree_set::IntoIter<T>
• impl<T> FusedIterator for std::vec::IntoIter<T>
• impl<'a, T> FusedIterator for std::collections::vec_deque::Iter<'a, T>
• impl<'a, T> FusedIterator for std::collections::vec_deque::IterMut<'a, T>
• impl<'a, T> FusedIterator for std::collections::btree_set::Iter<'a, T>
• impl<'a, T> FusedIterator for std::collections::linked_list::IterMut<'a, T>
• impl<'a, T> FusedIterator for std::collections::btree_set::Range<'a, T>
• impl<T> FusedIterator for std::collections::linked_list::IntoIter<T>
• impl<'a, T> FusedIterator for std::vec::Drain<'a, T>
• impl<K, V> FusedIterator for std::collections::btree_map::IntoIter<K, V>
• impl<'a, K, V> FusedIterator for std::collections::btree_map::Range<'a, K, V>
• impl<'a, T> FusedIterator for std::collections::linked_list::Iter<'a, T>
• impl<T> FusedIterator for std::collections::binary_heap::IntoIter<T>
• impl<'a, T> FusedIterator for std::collections::btree_set::SymmetricDifference<'a, T> where
    T: Ord, 
• impl<'a, K, V> FusedIterator for std::collections::btree_map::Iter<'a, K, V>
• impl<'a, T> FusedIterator for std::collections::btree_set::Intersection<'a, T> where
    T: Ord, 
• impl<'a, K, V> FusedIterator for RangeMut<'a, K, V>
• impl<'a, T> FusedIterator for std::collections::vec_deque::Drain<'a, T> where
    T: 'a, 
• impl FusedIterator for std::ascii::EscapeDefault
• impl<'a, K, V> FusedIterator for std::collections::hash_map::Iter<'a, K, V>
• impl<'a, K, V> FusedIterator for std::collections::hash_map::IterMut<'a, K, V>
• impl<K, V> FusedIterator for std::collections::hash_map::IntoIter<K, V>
• impl<'a, K, V> FusedIterator for std::collections::hash_map::Keys<'a, K, V>
• impl<'a, K, V> FusedIterator for std::collections::hash_map::Values<'a, K, V>
• impl<'a, K, V> FusedIterator for std::collections::hash_map::ValuesMut<'a, K, V>
• impl<'a, K, V> FusedIterator for std::collections::hash_map::Drain<'a, K, V>
• impl<'a, K> FusedIterator for std::collections::hash_set::Iter<'a, K>
• impl<K> FusedIterator for std::collections::hash_set::IntoIter<K>
• impl<'a, K> FusedIterator for std::collections::hash_set::Drain<'a, K>
• impl<'a, T, S> FusedIterator for std::collections::hash_set::Intersection<'a, T, S> where
    T: Eq + Hash,
    S: BuildHasher, 
• impl<'a, T, S> FusedIterator for std::collections::hash_set::Difference<'a, T, S> where
    T: Eq + Hash,
    S: BuildHasher, 
• impl<'a, T, S> FusedIterator for std::collections::hash_set::SymmetricDifference<'a, T, S> where
    T: Eq + Hash,
    S: BuildHasher, 
• impl<'a, T, S> FusedIterator for std::collections::hash_set::Union<'a, T, S> where
    T: Eq + Hash,
    S: BuildHasher, 
• impl<'a> FusedIterator for std::path::Iter<'a>
• impl<'a> FusedIterator for Components<'a>