Issue 6370: Performance issue with collections.Counter().
diff --git a/Lib/collections.py b/Lib/collections.py
index bd5d3e8..f255919 100644
--- a/Lib/collections.py
+++ b/Lib/collections.py
@@ -421,13 +421,15 @@
if iterable is not None:
if isinstance(iterable, Mapping):
if self:
+ self_get = self.get
for elem, count in iterable.items():
- self[elem] += count
+ self[elem] = count + self_get(elem, 0)
else:
dict.update(self, iterable) # fast path when counter is empty
else:
+ self_get = self.get
for elem in iterable:
- self[elem] += 1
+ self[elem] = 1 + self_get(elem, 0)
if kwds:
self.update(kwds)