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<i16>

impl TrustedLen for Range<u32>

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

impl TrustedLen for Range<i64>

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

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

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

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

impl TrustedLen for Range<u64>

impl TrustedLen for RangeInclusive<u32>

impl TrustedLen for Range<u8>

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

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

impl TrustedLen for RangeInclusive<i64>

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

impl TrustedLen for RangeInclusive<i8>

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

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

impl TrustedLen for RangeInclusive<u16>

impl TrustedLen for RangeInclusive<i32>

impl<T> TrustedLen for Empty<T>

impl TrustedLen for RangeInclusive<u8>

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

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

impl TrustedLen for Range<i32>

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

impl TrustedLen for Range<isize>

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

impl TrustedLen for RangeInclusive<i16>

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

impl<T> TrustedLen for Once<T>

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

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

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

impl TrustedLen for RangeInclusive<usize>

impl TrustedLen for Range<usize>

impl TrustedLen for Range<i8>

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

impl TrustedLen for Range<u16>

impl TrustedLen for RangeInclusive<u64>

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

impl TrustedLen for RangeInclusive<isize>

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

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

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

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

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

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