Add implementations of last in terms of next_back on a bunch of DoubleEndedIterators.

r?Manishearth

1 files changed, 5 insertions, 0 deletions

diff --git a/src/libcore/iter/adapters/mod.rs b/src/libcore/iter/adapters/mod.rs
index 3ab404a48d3..d814e8a5958 100644
--- a/src/libcore/iter/adapters/mod.rs
+++ b/src/libcore/iter/adapters/mod.rs
@@ -73,6 +73,11 @@ impl<I> Iterator for Rev<I> where I: DoubleEndedIterator {
     {
         self.iter.position(predicate)
     }
+
+    #[inline]
+    fn last(mut self) -> Option<Self::Item> {
+        self.next_back()
+    }
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]