Trait DoubleEndedLender 

pub trait DoubleEndedLender: Lender {
    // Required method
    fn next_back(&mut self) -> Option<Lend<'_, Self>>;

    // Provided methods
    fn advance_back_by(&mut self, n: usize) -> Result<(), NonZeroUsize> { ... }
    fn nth_back(&mut self, n: usize) -> Option<Lend<'_, Self>> { ... }
    fn try_rfold<B, F, R>(&mut self, init: B, f: F) -> R
       where F: FnMut(B, Lend<'_, Self>) -> R,
             R: Try<Output = B> { ... }
    fn rfold<B, F>(self, init: B, f: F) -> B
       where Self: Sized,
             F: FnMut(B, Lend<'_, Self>) -> B { ... }
    fn rfind<P>(&mut self, predicate: P) -> Option<Lend<'_, Self>>
       where Self: Sized,
             P: FnMut(&Lend<'_, Self>) -> bool { ... }
}

The Lender version of core::iter::DoubleEndedIterator.

Required Methods

fn next_back(&mut self) -> Option<Lend<'_, Self>>

Removes and returns a lend from the end of the lender.

Returns None when there are no more elements.

See DoubleEndedIterator::next_back.

Provided Methods

fn advance_back_by(&mut self, n: usize) -> Result<(), NonZeroUsize>

Advances the lender from the back by n elements.

See DoubleEndedIterator::advance_back_by.

fn nth_back(&mut self, n: usize) -> Option<Lend<'_, Self>>

Returns the nth element from the end of the lender.

See DoubleEndedIterator::nth_back.

fn try_rfold<B, F, R>(&mut self, init: B, f: F) -> R

where F: FnMut(B, Lend<'_, Self>) -> R, R: Try<Output = B>,

The reverse version of Lender::try_fold: it takes elements starting from the back of the lender.

See DoubleEndedIterator::try_rfold.

fn rfold<B, F>(self, init: B, f: F) -> B

where Self: Sized, F: FnMut(B, Lend<'_, Self>) -> B,

The reverse version of Lender::fold: it takes elements starting from the back of the lender.

See DoubleEndedIterator::rfold.

fn rfind<P>(&mut self, predicate: P) -> Option<Lend<'_, Self>>

where Self: Sized, P: FnMut(&Lend<'_, Self>) -> bool,

The reverse version of Lender::find: it searches for an element of the lender from the back that satisfies the predicate.

See DoubleEndedIterator::rfind.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementations on Foreign Types

impl<L: DoubleEndedLender> DoubleEndedLender for &mut L

fn next_back(&mut self) -> Option<Lend<'_, Self>>

fn advance_back_by(&mut self, n: usize) -> Result<(), NonZeroUsize>

fn nth_back(&mut self, n: usize) -> Option<Lend<'_, Self>>

Implementors

impl<'a, L> DoubleEndedLender for Repeat<'a, L>

where L: ?Sized + CovariantLending + 'a, for<'all> Lend<'all, L>: Clone,

impl<'a, L, F> DoubleEndedLender for RepeatWith<'a, L, F>

where L: ?Sized + CovariantLending + 'a, F: FnMut() -> Lend<'a, L>,

impl<'a, L, I> DoubleEndedLender for LendIter<'a, L, I>

where L: ?Sized + CovariantLending + 'a, I: DoubleEndedIterator<Item = Lend<'a, L>>,

impl<'this, L: DoubleEndedLender> DoubleEndedLender for Peekable<'this, L>

impl<A, B> DoubleEndedLender for Chain<A, B>

where A: DoubleEndedLender, B: DoubleEndedLender + for<'all> Lending<'all, Lend = Lend<'all, A>>,

impl<A, B> DoubleEndedLender for Zip<A, B>

where A: DoubleEndedLender + ExactSizeLender, B: DoubleEndedLender + ExactSizeLender,

impl<I: DoubleEndedIterator> DoubleEndedLender for FromIter<I>

impl<I: DoubleEndedIterator> DoubleEndedLender for FromIterRef<I>

impl<L> DoubleEndedLender for Empty<L>

where L: ?Sized + for<'all> Lending<'all>,

impl<L> DoubleEndedLender for Enumerate<L>

where L: ExactSizeLender + DoubleEndedLender,

impl<L> DoubleEndedLender for Fuse<L>

where L: DoubleEndedLender,

impl<L> DoubleEndedLender for Once<'_, L>

where L: ?Sized + CovariantLending,

impl<L> DoubleEndedLender for Rev<L>

where L: DoubleEndedLender,

impl<L> DoubleEndedLender for Skip<L>

where L: DoubleEndedLender + ExactSizeLender,

impl<L> DoubleEndedLender for StepBy<L>

where L: DoubleEndedLender + ExactSizeLender,

impl<L> DoubleEndedLender for Take<L>

where L: DoubleEndedLender + ExactSizeLender,

impl<L, F> DoubleEndedLender for FilterMap<L, F>

where for<'all> F: FnMutHKAOpt<'all, Lend<'all, L>>, L: DoubleEndedLender,

impl<L, F> DoubleEndedLender for Inspect<L, F>

where L: DoubleEndedLender, F: FnMut(&Lend<'_, L>),

impl<L, F> DoubleEndedLender for Mutate<L, F>

where L: DoubleEndedLender, F: FnMut(&mut Lend<'_, L>),

impl<L, P> DoubleEndedLender for Filter<L, P>

where P: FnMut(&Lend<'_, L>) -> bool, L: DoubleEndedLender,

impl<L: DoubleEndedLender, F> DoubleEndedLender for Map<L, F>

where F: for<'all> FnMutHKA<'all, Lend<'all, L>>,

impl<St, F> DoubleEndedLender for OnceWith<St, F>

where F: for<'all> FnOnceHKA<'all, &'all mut St>,

impl<T> DoubleEndedLender for WindowsMut<'_, T>

impl<T, const WINDOW_SIZE: usize> DoubleEndedLender for ArrayWindowsMut<'_, T, WINDOW_SIZE>