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