From: Raymond Hettinger <rhettinger@users.noreply.github.com>
Date: Tue, 21 Nov 2017 08:23:34 +0000 (-0800)
Subject: Add comment and improve variable name in roundrobin() (#4486)
X-Git-Tag: v3.7.0a3~130
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=337cbbace0a43f50fcd33ea4d3b7cb30733237db;p=python

Add comment and improve variable name in roundrobin() (#4486)
---

diff --git a/Doc/library/itertools.rst b/Doc/library/itertools.rst
index fa6c340bb7..a91894059d 100644
--- a/Doc/library/itertools.rst
+++ b/Doc/library/itertools.rst
@@ -753,15 +753,16 @@ which incur interpreter overhead.
    def roundrobin(*iterables):
        "roundrobin('ABC', 'D', 'EF') --> A D E B F C"
        # Recipe credited to George Sakkis
-       pending = len(iterables)
+       num_active = len(iterables)
        nexts = cycle(iter(it).__next__ for it in iterables)
-       while pending:
+       while num_active:
            try:
                for next in nexts:
                    yield next()
            except StopIteration:
-               pending -= 1
-               nexts = cycle(islice(nexts, pending))
+               # Remove the iterator we just exhausted from the cycle.
+               num_active -= 1
+               nexts = cycle(islice(nexts, num_active))
 
    def partition(pred, iterable):
        'Use a predicate to partition entries into false entries and true entries'