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