From: Raymond Hettinger <python@rcn.com>
Date: Sat, 23 Feb 2008 10:04:15 +0000 (+0000)
Subject: Add recipe using itertools.product().
X-Git-Tag: v2.6a1~109
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=7832d4d534ff7105a0253694db734d5007b62e91;p=thirdparty%2FPython%2Fcpython.git

Add recipe using itertools.product().
---

diff --git a/Doc/library/itertools.rst b/Doc/library/itertools.rst
index 7d1ec9664056..5cc3e08fa826 100644
--- a/Doc/library/itertools.rst
+++ b/Doc/library/itertools.rst
@@ -559,3 +559,9 @@ which incur interpreter overhead. ::
                pending -= 1
                nexts = cycle(islice(nexts, pending))
 
+   def powerset(iterable):
+       "powerset('ab') --> set([]), set(['b']), set(['a']), set(['a', 'b'])"
+       skip = object()
+       for t in product(*izip(repeat(skip), iterable)):
+           yield set(e for e in t if e is not skip)
+