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Groups > comp.lang.python > #10958

Calling super() in __init__ of a metaclass

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Consider this standard metaclass definition:

class MyMetaclass(type):
    def __init__(cls, name, bases, dct):
        super(MyMetaclass, cls).__init__(name, bases, dct)
        # do meta-stuff

class Foo(object):
    __metaclass__ = MyMetaclass

The call "super(MyMetaclass, cls)" should returns the parent of
MyMetaclass here. But the 'cls' passed into this __init__ is *not*
MyMetaclass, but rather the created class - i.e. Foo. So how does
"super" get to the parent of MyMetaclass using this information? The
documentation of "super" says:

    If the second argument is a type, issubclass(type2, type) must be
true (this is useful for classmethods).

Yes, 'cls' is a type (it's "class Foo"), but no, it's not a subclass
of MyMetaclass, so this doesn't help.

Eli

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Calling super() in __init__ of a metaclass Eli Bendersky <eliben@gmail.com> - 2011-08-06 10:34 +0300
  Re: Calling super() in __init__ of a metaclass Peter Otten <__peter__@web.de> - 2011-08-06 10:11 +0200

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