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