merge

1 files changed, 11 insertions, 0 deletions

diff --git a/itertoolset.py b/itertoolset.py
index bd4e45c..9d5200c 100644
--- a/itertoolset.py
+++ b/itertoolset.py
@@ -1,4 +1,5 @@
 from itertools import *
+import collections
 
 def roundrobin(*iterables):
     """roundrobin('ABC', 'D', 'EF') --> A D E B F C"""
@@ -36,3 +37,13 @@ def ncycles(iterable, n):
 def take(n, iterable):
     "Return first n items of the iterable as a list"
     return list(islice(iterable, n))
+
+def consume(iterator, n=None):
+    "Advance the iterator n-steps ahead. If n is none, consume entirely."
+    # 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 empty slice starting at position n
+        next(islice(iterator, n, n), None)