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Date: Thu, 16 Aug 2012 19:27:34 +0200
From: Thomas Bach <thbach@students.uni-mainz.de>
To: <python-list@python.org>
Subject: Re: Dynamically determine base classes on instantiation
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Xref: csiph.com comp.lang.python:27186

On Thu, Aug 16, 2012 at 10:03:51AM -0700, Richard Thomas wrote:
> class Foo(object):
>     def __new__(cls, arg):
>         if isinstance(arg, list):
>             cls = FooList
>         elif isinstance(arg, dict):
>             cls = FooDict
>         return object.__new__(cls, arg)
> 
> class FooList(Foo, list):
>     pass
> 
> class FooDict(Foo, dict):
>     pass
> 
> You could even have __new__ make these Foo* classes dynamically when
> it encounters a new type of argument.
> 
> Chard.

Thanks for that one. Your solution just hit me like a punch in the
face. I had something similar in my mind. But I could not work out how
the mechanics behind it are working.

Regards,

	Thomas