Alex Gaynor added the comment: d[key] += 1 still does two dict lookups, and invokes the hash function twice:
>>> class X(object): ... def __hash__(self): ... print "hashed" ... return 0 ... def __eq__(self, other): ... return True ... >>> d = {X(): 0} hashed >>> d[X()] hashed 0 >>> d[X()] = 3 hashed >>> d[X()] += 1 hashed hashed ---------- _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue21101> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com