castironpi at castironpi at
Tue Mar 4 06:31:10 CET 2008

On Mar 3, 10:01 pm, Benjamin <musiccomposit... at> wrote:
> On Mar 3, 7:12 pm, castiro... at wrote:
> > What are metaclasses?
> Depends on whether you want to be confused or not. If you do, look at
> this old but still head bursting essay:
> Basically, the metaclass of a (new-style) class is responsible for
> creating the class. This means when Python sees
> class Foo(object):
>     __metaclass__ = FooMeta
> class FooMeta(type):
>     def __new__(cls, name, bases, dct):
>        #do something cool to the class
>        pass
> It asks FooMeta to create the class Foo. Metaclasses always extend
> type because type is the default metaclass.

But you can stack class decorations, but not class metas.

class Foo:

* class Foo:
   __metaclass__= MetaCool1, MetaCool

* denotes malformed

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