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

impl TrustedLen for RangeInclusive<i16>

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

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

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

impl TrustedLen for Range<i64>

impl TrustedLen for Range<i32>

impl TrustedLen for Range<i8>

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

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

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

impl TrustedLen for Range<u16>

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

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

impl TrustedLen for RangeInclusive<i64>

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

impl TrustedLen for Range<i16>

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

impl TrustedLen for RangeInclusive<u16>

impl TrustedLen for Range<u64>

impl TrustedLen for Range<isize>

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

impl TrustedLen for RangeInclusive<i8>

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

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

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

impl TrustedLen for Range<u32>

impl TrustedLen for Range<usize>

impl TrustedLen for RangeInclusive<usize>

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

impl TrustedLen for RangeInclusive<isize>

impl TrustedLen for RangeInclusive<u8>

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

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

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

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

impl<T> TrustedLen for Empty<T>

impl TrustedLen for RangeInclusive<u32>

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

impl TrustedLen for Range<u8>

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

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

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

impl TrustedLen for RangeInclusive<u64>

impl<T> TrustedLen for Once<T>

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

impl TrustedLen for RangeInclusive<i32>

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