Add comment and improve variable name in roundrobin() (#4486)
diff --git a/Doc/library/itertools.rst b/Doc/library/itertools.rst
index fa6c340..a918940 100644
--- a/Doc/library/itertools.rst
+++ b/Doc/library/itertools.rst
@@ -753,15 +753,16 @@
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'