On Jun 22, 2010, at 5:48 AM, Benjamin Peterson wrote: > 2010/6/22 Raymond Hettinger <raymond.hettin...@gmail.com>: >> There's an entry in whatsnew for 2.7 to the effect of "The UserDict class is >> now a new-style class". >> I had thought there was a conscious decision to not change any existing >> classes from old-style to new-style. IIRC, Martin had championed this idea >> and had rejected all of proposals to make existing classes inherit from >> object. > > IIRC this was because UserDict tries to be a MutableMapping but abcs > require new style classes.
ISTM, this change should be reverted to the way it was in 2.6. The registration was already working fine: Python 2.6.4 (r264:75821M, Oct 27 2009, 19:48:32) [GCC 4.0.1 (Apple Inc. build 5493)] on darwin >>> import UserDict >>> import collections >>> collections.MutableMapping.register(UserDict.UserDict) >>> issubclass(UserDict.UserDict, collections.MutableMapping) True We've didn't have any problems with this registration nor did there seem to be an issue with UserDict not implementing dictviews. Please revert this change. UserDicts have a long history and are used by a lot of code, so we need to avoid unnecessary breakage. Thank you, Raymond _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
