Trait std::iter::ExactSize
pub trait ExactSize<A>: DoubleEndedIterator<A> {
fn rposition(&mut self, predicate: |A| -> bool) -> Option<uint> { ... }
}An iterator that knows its exact length
This trait is a helper for iterators like the vector iterator, so that it can support double-ended enumeration.
Iterator::size_hint must return the exact size of the iterator.
Note that the size must fit in uint.
Provided Methods
fn rposition(&mut self, predicate: |A| -> bool) -> Option<uint>
Return the index of the last element satisfying the specified predicate
If no element matches, None is returned.