[Python-ideas] A (meta)class algebra

[Antony Lee]

Create the required inheriting metaclass on the fly:

def multi_meta(*clss):
    """A helper for inheriting from classes with different metaclasses.

    Usage:
        class C(multi_meta(A, B)):
            "A class inheriting from classes A, B with different
metaclasses."
    """
    mcss = tuple(type(cls) for cls in clss)
    mcs = type(
        "Meta[{}]".format(", ".join(mcs.__name__ for mcs in mcss)), mcss,
{})
    return mcs("[{}]".format(", ".join(cls.__name__ for cls in clss)),
clss, {})

I have the same use-case as you, i.e. mixing custom metaclasses with
QObjects.

2015-02-12 10:36 GMT-08:00 Ethan Furman <ethan at stoneleaf.us>:

> On 02/12/2015 05:42 AM, Martin Teichmann wrote:
>
> > class MetaQRegistrar(MetaRegistrar, type(QObject)):
> >     pass
> >
> > but then you always have to write something like
> >
> > class Spam(Registrar, QObject, metaclass=MetaQRegistrar):
> >     pass
>
> or:
>
>   class RQObject(metaclass=MetaQRegistrar):
>       pass
>
>   class Spam(RQObject):
>       pass
>
> --
> ~Ethan~
>
>
> _______________________________________________
> Python-ideas mailing list
> Python-ideas at python.org
> https://mail.python.org/mailman/listinfo/python-ideas
> Code of Conduct: http://python.org/psf/codeofconduct/
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-ideas/attachments/20150212/ef33d8da/attachment.html>