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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Mon, 19 Dec 2011 20:46:29 -0700
Subject: Re: Grammar for classes
To: Joshua Landau <joshua.landau.ws@gmail.com>
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On Mon, Dec 19, 2011 at 6:34 PM, Joshua Landau
<joshua.landau.ws@gmail.com> wrote:
> In reading thorough the syntax defined in the reference, the class statem=
ent
> has=A0surprised=A0me.
>
> It says that the inheritance part of the class can accept comprehensions.
> What does this mean?
> I've tried:
> "class A(x for x in ()): pass"
> but this doesn't need the extra clause as "x for x in ()" is an expressio=
n,
> and thus this evaluates:
> "class A(x for x in (),): pass"
> although again it won't be a valid class anytime soon.
>
> So what is this clause for?

That's new to me as well.  There's nothing about it in PEP 3115.  I
suspect it's a bad copy-and-paste from the function call syntax.