[Python-3000] PEP 3124 - Overloading, Generic Functions, Interfaces, etc. (original) (raw)

Jim Jewett jimjjewett at gmail.com
Tue May 1 01:29:30 CEST 2007

On 4/30/07, Phillip J. Eby <pje at telecommunity.com> wrote:

It is currently an open issue to determine the best way to implement this rule in Python 3.0. Under Python 2.x, a class' metaclass was not chosen until the end of the class body, which means that decorators could insert a custom metaclass to do processing of this sort. (This is how RuleDispatch, for example, implements the implicit class rule.)

PEP 3115, however, requires that a class' metaclass be determined before the class body has executed, making it impossible to use this technique for class decoration any more.

It doesn't say what that metaclass has to do, though.

Is there any reason the metaclass couldn't delegate differently depending on the value of my_magic_attribute ?

-jJ

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