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