pub trait DoubleEndedStreamingIterator: StreamingIterator {
    fn advance_back(&mut self);

    fn next_back(&mut self) -> Option<&Self::Item> { ... }
    fn rfold<B, F>(self, init: B, f: F) -> B
    where
        Self: Sized,
        F: FnMut(B, &Self::Item) -> B
, { ... } }
Expand description

A streaming iterator able to yield elements from both ends.

Required Methods§

Advances the iterator to the next element from the back of the iterator.

Double ended iterators just after the last element, so this should be called before get when iterating in reverse.

The behavior of calling this method after the iterator has been exhausted is unspecified.

Provided Methods§

Advances the iterator and returns the next value from the back.

The behavior of calling this method after the iterator has been exhausted is unspecified.

The default implementation simply calls advance_back followed by get.

Reduces the iterator’s elements to a single, final value, starting from the back.

Implementors§