On 3/8/07, Talin <[EMAIL PROTECTED]> wrote: > First, there is a purely cosmetic argument about how metaclasses ought > to be specified syntactically, which I won't go into in any detail. Most > of the proposals centered around what I will call 'Class Definition > Keyword Arguments' (CDKA), in other words keyword arguments that are > passed in along with the list of base classes.
You need to in the PEP though, particularly since class decorators are now available. (These remove the need for some of the existing metaclass usage.) > ... a means to > supply a custom, dictionary-like object that would be used to collect > the class member definitions as the class was being evaluated. ... > Now, it was pointed out that the only use cases for a custom dictionary > that anyone could think of were all about preserving the ordering of > declarations. Not quite true. (1) immutable class dictionaries. These are typical for extension classes, but a real pain for python classes. (2) almost-immutable -- with callbacks when values are added/changed/deleted. PJE just pointed out that doing this on even just the __bases__ attribute could make generic functions safer. (3) actually-private variables -jJ _______________________________________________ Python-3000 mailing list [email protected] http://mail.python.org/mailman/listinfo/python-3000 Unsubscribe: http://mail.python.org/mailman/options/python-3000/archive%40mail-archive.com
