Stephen Webber added the comment:
Hmm, that is odd behavior indeed.
I think having keys that point to zero values is important for iterating over a
set. For example:
>>> x = Counter(a=10, b=0)
>>> for k in set(x):
... x[k] += 1
...
>>> x
Counter({'a':
Stephen Webber added the comment:
This is intentional handling of non-existant variables, and is not resticted to
'==' operations. Returning the value of a Counter parameter that has not yet
been set returns 0 by default.
See the documentation here:
http://docs.python.o
