Trait std::iter::TrustedLen

pub unsafe trait TrustedLen: Iterator { }

🔬 This is a nightly-only experimental API. (trusted_len #37572)

An iterator that reports an accurate length using size_hint.

The iterator reports a size hint where it is either exact (lower bound is equal to upper bound), or the upper bound is None. The upper bound must only be None if the actual iterator length is larger than usize::MAX. In that case, the lower bound must be usize::MAX, resulting in a .size_hint of (usize::MAX, None).

The iterator must produce exactly the number of elements it reported or diverge before reaching the end.

Safety

This trait must only be implemented when the contract is upheld. Consumers of this trait must inspect .size_hint’s upper bound.

Implementors

impl TrustedLen for Range<u64>

impl TrustedLen for Range<i8>

impl<'a, I> TrustedLen for &'a mut I where     I: TrustedLen + ?Sized,

impl TrustedLen for Range<u8>

impl<'a, T> TrustedLen for std::slice::IterMut<'a, T>

impl<'a, T> TrustedLen for Windows<'a, T>

impl<A, F> TrustedLen for RepeatWith<F> where     F: FnMut() -> A,

impl TrustedLen for Range<isize>

impl<T> TrustedLen for Once<T>

impl<'a, T> TrustedLen for std::slice::Iter<'a, T>

impl TrustedLen for Range<usize>

impl<I> TrustedLen for Rev<I> where     I: TrustedLen + DoubleEndedIterator,

impl<'a, T> TrustedLen for ExactChunksMut<'a, T>

impl<A> TrustedLen for Repeat<A> where     A: Clone,

impl TrustedLen for RangeInclusive<i32>

impl TrustedLen for RangeInclusive<u8>

impl TrustedLen for RangeInclusive<u32>

impl TrustedLen for Range<u32>

impl<'a> TrustedLen for Bytes<'a>

impl TrustedLen for RangeInclusive<i8>

impl<I> TrustedLen for Enumerate<I> where     I: TrustedLen,

impl<A, B> TrustedLen for Zip<A, B> where     A: TrustedLen,     B: TrustedLen,

impl TrustedLen for RangeInclusive<isize>

impl TrustedLen for Range<u16>

impl<A> TrustedLen for std::result::IntoIter<A>

impl<I> TrustedLen for Take<I> where     I: TrustedLen,

impl<'a, A> TrustedLen for std::result::Iter<'a, A>

impl<A> TrustedLen for RangeFrom<A> where     A: Step,

impl<'a, A> TrustedLen for std::option::Iter<'a, A>

impl<'a, A> TrustedLen for std::option::IterMut<'a, A>

impl<B, I, F> TrustedLen for Map<I, F> where     F: FnMut(<I as Iterator>::Item) -> B,     I: TrustedLen,

impl<'a, A> TrustedLen for std::result::IterMut<'a, A>

impl<'a, T> TrustedLen for ExactChunks<'a, T>

impl<'a, T> TrustedLen for Chunks<'a, T>

impl<T> TrustedLen for Empty<T>

impl<A> TrustedLen for std::option::IntoIter<A>

impl TrustedLen for RangeInclusive<u16>

impl<'a, I, T> TrustedLen for Cloned<I> where     I: TrustedLen<Item = &'a T>,     T: 'a + Clone,

impl TrustedLen for Range<i32>

impl TrustedLen for RangeInclusive<i64>

impl<A, B> TrustedLen for Chain<A, B> where     A: TrustedLen,     B: TrustedLen<Item = <A as Iterator>::Item>,

impl TrustedLen for RangeInclusive<usize>

impl<'a, T> TrustedLen for ChunksMut<'a, T>

impl TrustedLen for RangeInclusive<i16>

impl TrustedLen for RangeInclusive<u64>

impl TrustedLen for Range<i16>

impl TrustedLen for Range<i64>

impl<T> TrustedLen for std::vec::IntoIter<T>