[Python-checkins] cpython: Issue 16774: Add a new itertools recipe (suggested by Alexey Kachayev).

[raymond.hettinger]

http://hg.python.org/cpython/rev/2781fb146f4a
changeset:   90838:2781fb146f4a
user:        Raymond Hettinger <python at rcn.com>
date:        Sun May 25 22:03:56 2014 -0700
summary:
  Issue 16774:  Add a new itertools recipe (suggested by Alexey Kachayev).

files:
  Doc/library/itertools.rst |  5 +++++
  1 files changed, 5 insertions(+), 0 deletions(-)


diff --git a/Doc/library/itertools.rst b/Doc/library/itertools.rst
--- a/Doc/library/itertools.rst
+++ b/Doc/library/itertools.rst
@@ -662,6 +662,11 @@
        "Return function(0), function(1), ..."
        return map(function, count(start))
 
+   def tail(n, iterable):
+       "Return an iterator over the last n items"
+       # tail(3, 'ABCDEFG') --> E F G
+       return iter(collections.deque(iterable, maxlen=n))
+
    def consume(iterator, n):
        "Advance the iterator n-steps ahead. If n is none, consume entirely."
        # Use functions that consume iterators at C speed.

-- 
Repository URL: http://hg.python.org/cpython