[Python-3000] metaclass syntax [was: Discussions with no PEPs]

[Jim Jewett]

(reasons to use a custom dict, other than ordering)
> > (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.

> > (3)  actually-private variables

On 3/9/07, Guido van Rossum <guido at python.org> wrote:
> Those look like use cases for metaclasses, but I don't see how
> they require setting a custom dict *while the class suite is being
> executed*.

I was thinking too much of attempts to subclass module.  The newly
created objects retain a reference to the original dictionary as their
globals.  I should at least have made that assumption clear.

-jJ