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Date: Mon, 4 Jul 2011 13:09:52 -0700
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Subject: Re: [Python-ideas] Allow isinstance second argument to be a set of types
From: Chris Rebert <clp2@rebertia.com>
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:8791

On Mon, Jul 4, 2011 at 12:53 PM, MRAB <python@mrabarnett.plus.com> wrote:
> On 04/07/2011 20:41, Amaury Forgeot d'Arc wrote:
>>> Le lundi 04 juillet 2011 =C3=A0 10:52 -0700, Gregory P. Smith a =C3=A9c=
rit :
>>>>
>>>> note that a fast lookup implies exact type and not subclass making my
>>>> point silly... at which point you're back to iterating so I suspect
>>>> supporting arbitrary iterables is actually how this will be
>>>> implemented regardless.
>>
>> Arbitrary iterables, arbitrarily nested...
>> beware of objects which are also their first element, like str('a')...
>>
> Probably not arbitrarily nested, just a type (type(t) is type) or an
> iterable yielding types. Anything else would raise an exception.

What about a type that is itself iterable (via metaclass magic)?
Gotta consider the wacky edge cases.

Cheers,
Chris