[Python-Dev] UserDict in 2.7 (original) (raw)

Benjamin Peterson benjamin at python.org
Tue Jun 22 19:08:02 CEST 2010

2010/6/22 Raymond Hettinger <raymond.hettinger at gmail.com>:

On Jun 22, 2010, at 5:48 AM, Benjamin Peterson wrote:

2010/6/22 Raymond Hettinger <raymond.hettinger at 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:

Actually I believe it was an error that it could. There was a typo in abc.py which prevented it from raising errors when non new-style class objects were passed in.

-- Regards, Benjamin

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