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.

The iterator must produce exactly the number of elements it reported.

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<T> TrustedLen for std::vec::IntoIter<T>
• impl TrustedLen for Range<i32>
• impl TrustedLen for RangeInclusive<u32>
• 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 TrustedLen for RangeInclusive<i64>
• impl<A> TrustedLen for std::result::IntoIter<A>
• impl TrustedLen for Range<u16>
• impl TrustedLen for Range<u64>
• impl TrustedLen for RangeInclusive<u8>
• impl TrustedLen for Range<i8>
• impl TrustedLen for RangeInclusive<isize>
• impl TrustedLen for Range<i64>
• impl<T> TrustedLen for Empty<T>
• impl<A, B> TrustedLen for Chain<A, B> where
    A: TrustedLen,
    B: TrustedLen<Item = <A as Iterator>::Item>, 
• impl<'a, I> TrustedLen for &'a mut I where
    I: TrustedLen + ?Sized, 
• impl<'a, T> TrustedLen for std::slice::Iter<'a, T>
• impl<T> TrustedLen for Once<T>
• impl TrustedLen for Range<u8>
• impl<'a, A> TrustedLen for std::option::Iter<'a, A>
• impl TrustedLen for RangeInclusive<u16>
• impl TrustedLen for Range<i16>
• impl TrustedLen for RangeInclusive<i8>
• impl<'a, T> TrustedLen for std::slice::IterMut<'a, T>
• impl<'a, A> TrustedLen for std::option::IterMut<'a, A>
• impl TrustedLen for Range<u32>
• impl<'a> TrustedLen for Bytes<'a>
• impl TrustedLen for Range<isize>
• impl TrustedLen for RangeInclusive<i32>
• impl<'a, I, T> TrustedLen for Cloned<I> where
    I: TrustedLen<Item = &'a T>,
    T: 'a + Clone, 
• impl<I> TrustedLen for Enumerate<I> where
    I: TrustedLen, 
• impl<'a, A> TrustedLen for std::result::Iter<'a, A>
• impl TrustedLen for RangeInclusive<usize>
• impl TrustedLen for RangeInclusive<i16>
• impl TrustedLen for RangeInclusive<u64>
• impl TrustedLen for Range<usize>
• impl<A> TrustedLen for std::option::IntoIter<A>
• impl<'a, A> TrustedLen for std::result::IterMut<'a, A>