At 09:13 PM 7/13/2007 +0200, Thomas Heller wrote: >playing a little with py3k... > >pep3115 mentions that "__prepare__ returns a dictionary-like object >which is used to store the class member definitions during evaluation >of the class body." > >It does not mention whether this dict-like object is used afterwards >as the class-dictionary of the created class or not (when the __new__ >method of the metaclass is called). > >The sample-code suggests that it would be used as class dict of the >newly created class (the sample code copies it into a regular dictionary >before it is passed to the type.__new__ call). >However, the actual code in the py3k-struni branch (typeobject.c) copies >the passed in dict again. > >In other words, it seems impossible even with pep3115 to use a custom >subclass of dict as a type's __dict__ member, and afaik it is impossible >in Python to replace that afterwards. > >Is this analysis correct? Is that the intent of pep3115? Or could >the code be changed so that it is possible to supply a custom type dict >with the metaclass?
I would suggest that we do not intend that the class __dict__ == the __prepare__ object, even as the default case. Otherwise, we have to find everything that accesses type dictionaries and make sure they can work with other kinds of objects. _______________________________________________ Python-3000 mailing list Python-3000@python.org http://mail.python.org/mailman/listinfo/python-3000 Unsubscribe: http://mail.python.org/mailman/options/python-3000/archive%40mail-archive.com
