Update itertools recipe for consume().
diff --git a/Doc/library/itertools.rst b/Doc/library/itertools.rst
index 4f82a27..f83e976 100644
--- a/Doc/library/itertools.rst
+++ b/Doc/library/itertools.rst
@@ -672,7 +672,13 @@
def consume(iterator, n):
"Advance the iterator n-steps ahead. If n is none, consume entirely."
- collections.deque(islice(iterator, n), maxlen=0)
+ # Use functions that consume iterators at C speed.
+ if n is None:
+ # feed the entire iterator into a zero-length deque
+ collections.deque(iterator, maxlen=0)
+ else:
+ # advance to the emtpy slice starting at position n
+ next(islice(iterator, n, n), None)
def nth(iterable, n, default=None):
"Returns the nth item or a default value"