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.

Implementors

• impl FusedIterator for ToLowercase
• impl<I> FusedIterator for Utf16Encoder<I> where
    I: FusedIterator<Item = char>, 
• impl<'a> FusedIterator for SplitWhitespace<'a>
• impl FusedIterator for ToUppercase
• impl<'a, T, P> FusedIterator for SplitNMut<'a, T, P> where
    P: FnMut(&T) -> bool, 
• impl<'a, T, P> FusedIterator for RSplitNMut<'a, T, P> where
    P: FnMut(&T) -> bool, 
• impl<I, F> FusedIterator for Inspect<I, F> where
    F: FnMut(&<I as Iterator>::Item) -> (),
    I: FusedIterator, 
• impl<'a> FusedIterator for Bytes<'a>
• impl<I, P> FusedIterator for TakeWhile<I, P> where
    I: FusedIterator,
    P: FnMut(&<I as Iterator>::Item) -> bool, 
• impl<'a> FusedIterator for LinesAny<'a>
• impl<A, B> FusedIterator for Zip<A, B> where
    A: FusedIterator,
    B: FusedIterator, 
• impl<'a, T, P> FusedIterator for RSplitMut<'a, T, P> where
    P: FnMut(&T) -> bool, 
• impl<'a, T> FusedIterator for std::slice::IterMut<'a, T>
• impl FusedIterator for EscapeDebug
• impl<I> FusedIterator for Rev<I> where
    I: FusedIterator + DoubleEndedIterator, 
• impl<'a, P> FusedIterator for std::str::Split<'a, P> where
    P: Pattern<'a>, 
• impl<'a, T, P> FusedIterator for std::slice::RSplitN<'a, T, P> where
    P: FnMut(&T) -> bool, 
• impl<I> FusedIterator for DecodeUtf8<I> where
    I: FusedIterator<Item = u8>, 
• impl<'a, T> FusedIterator for Chunks<'a, T>
• impl<'a, P> FusedIterator for Matches<'a, P> where
    P: Pattern<'a>, 
• impl<A> FusedIterator for std::ops::Range<A> where
    A: Step, 
• impl<'a, P> FusedIterator for RSplitTerminator<'a, P> where
    P: Pattern<'a>,
    <P as Pattern<'a>>::Searcher: ReverseSearcher<'a>, 
• impl<I, P> FusedIterator for Filter<I, P> where
    I: FusedIterator,
    P: FnMut(&<I as Iterator>::Item) -> bool, 
• impl<'a, T> FusedIterator for Windows<'a, T>
• 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 std::result::Iter<'a, T>
• impl<'a, P> FusedIterator for SplitTerminator<'a, P> where
    P: Pattern<'a>, 
• impl<T> FusedIterator for std::result::IntoIter<T>
• impl<'a> FusedIterator for CharIndices<'a>
• 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 std::str::SplitN<'a, P> where
    P: Pattern<'a>, 
• impl<A> FusedIterator for RangeInclusive<A> where
    A: Step, 
• impl<'a, T> FusedIterator for std::result::IterMut<'a, T>
• impl<'a, P> FusedIterator for RMatches<'a, P> where
    P: Pattern<'a>,
    <P as Pattern<'a>>::Searcher: ReverseSearcher<'a>, 
• impl<'a, T> FusedIterator for ChunksMut<'a, T>
• impl<I> FusedIterator for Enumerate<I> where
    I: FusedIterator, 
• impl<A, B> FusedIterator for Chain<A, B> where
    A: FusedIterator,
    B: FusedIterator<Item = <A as Iterator>::Item>, 
• impl<'a, I, T> FusedIterator for Cloned<I> where
    I: FusedIterator<Item = &'a T>,
    T: 'a + Clone, 
• impl<'a, A> FusedIterator for std::option::Iter<'a, A>
• impl<'a, I> FusedIterator for &'a mut I where
    I: FusedIterator + ?Sized, 
• impl<'a, A> FusedIterator for std::option::IterMut<'a, A>
• impl<I> FusedIterator for Fuse<I> where
    I: Iterator, 
• impl<'a, T, P> FusedIterator for std::slice::Split<'a, T, P> where
    P: FnMut(&T) -> bool, 
• impl FusedIterator for std::char::EscapeDefault
• impl<'a, P> FusedIterator for MatchIndices<'a, P> where
    P: Pattern<'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, T, P> FusedIterator for std::slice::RSplit<'a, T, P> where
    P: FnMut(&T) -> bool, 
• impl<I> FusedIterator for Cycle<I> where
    I: Clone + Iterator, 
• impl<I, P> FusedIterator for SkipWhile<I, P> where
    I: FusedIterator,
    P: FnMut(&<I as Iterator>::Item) -> bool, 
• impl<'a, T, P> FusedIterator for SplitMut<'a, T, P> where
    P: FnMut(&T) -> bool, 
• impl<'a> FusedIterator for Lines<'a>
• impl<I> FusedIterator for Skip<I> where
    I: FusedIterator, 
• impl<B, I, F> FusedIterator for Map<I, F> where
    F: FnMut(<I as Iterator>::Item) -> B,
    I: FusedIterator, 
• 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 std::option::IntoIter<A>
• impl<I> FusedIterator for Take<I> where
    I: FusedIterator, 
• impl<'a, T> FusedIterator for std::slice::Iter<'a, T>
• impl FusedIterator for EscapeUnicode
• impl<'a, P> FusedIterator for RMatchIndices<'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 Chars<'a>
• impl<A> FusedIterator for RangeFrom<A> where
    A: Step, 
• impl<B, I, F> FusedIterator for FilterMap<I, F> where
    F: FnMut(<I as Iterator>::Item) -> Option<B>,
    I: FusedIterator, 
• impl<T> FusedIterator for Empty<T>
• impl<A> FusedIterator for Repeat<A> where
    A: Clone, 
• 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<'a, K, V> FusedIterator for std::collections::btree_map::IterMut<'a, K, V>
• impl<'a, T> FusedIterator for std::vec::Drain<'a, T>
• impl<I> FusedIterator for Box<I> where
    I: FusedIterator + ?Sized, 
• impl<'a, T> FusedIterator for std::collections::vec_deque::Drain<'a, T> where
    T: 'a, 
• impl<'a, T> FusedIterator for std::collections::vec_deque::Iter<'a, T>
• impl<'a, T> FusedIterator for std::collections::btree_set::Range<'a, T>
• impl<'a, T> FusedIterator for std::collections::btree_set::Difference<'a, T> where
    T: Ord, 
• impl<K, V> FusedIterator for std::collections::btree_map::IntoIter<K, V>
• impl<'a, K, V> FusedIterator for std::collections::btree_map::Iter<'a, K, V>
• 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<T> FusedIterator for std::collections::binary_heap::IntoIter<T>
• impl<'a, T> FusedIterator for std::collections::vec_deque::IterMut<'a, T>
• impl<'a, T> FusedIterator for std::collections::btree_set::Union<'a, T> where
    T: Ord, 
• impl<'a> FusedIterator for std::string::Drain<'a>
• impl<T> FusedIterator for std::collections::vec_deque::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<T> FusedIterator for std::collections::btree_set::IntoIter<T>
• impl<T> FusedIterator for std::collections::linked_list::IntoIter<T>
• impl<'a, T> FusedIterator for std::collections::binary_heap::Iter<'a, T>
• impl<'a, T> FusedIterator for std::collections::linked_list::IterMut<'a, T>
• impl<'a, T> FusedIterator for std::collections::binary_heap::Drain<'a, T> where
    T: 'a, 
• impl<'a, T> FusedIterator for std::collections::btree_set::Iter<'a, T>
• impl<T> FusedIterator for std::vec::IntoIter<T>
• impl<'a> FusedIterator for EncodeUtf16<'a>
• impl<'a, T> FusedIterator for std::collections::linked_list::Iter<'a, T>
• impl<'a, T> FusedIterator for std::collections::btree_set::Intersection<'a, T> where
    T: Ord, 
• 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>