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Date: Wed, 26 Jun 2013 13:37:37 -0700
From: Ethan Furman <ethan@stoneleaf.us>
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Subject: Re: What is the semantics meaning of 'object'?
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Xref: csiph.com comp.lang.python:49276

On 06/23/2013 12:05 PM, Ian Kelly wrote:
> On Sun, Jun 23, 2013 at 12:46 PM, Steven D'Aprano
> <steve+comp.lang.python@pearwood.info> wrote:
>> All is not lost, there are ways to make your classes cooperative. The
>> trick is to have your classes' __init__ methods ignore keyword arguments
>> they don't know what to do with. object used to do the same thing, but it
>> no longer does, so you need to add an extra class just before object to
>> swallow any args before they read object.
>>
>>
>> class Blocker(object):
>>      def __init__(self, **kwargs):
>>          # Block kwargs from reaching object
>>          super(Blocker, self).__init__()
>
> I don't like the idea of doing this with a cooperative __init__
> method.  If any keyword arguments were passed that weren't consumed,
> that is probably a bug, and this just swallows the exception instead
> of reporting it.

+1

Z
> Of course, if you're doing cooperative inheritance with some other
> method that doesn't exist on object, then this technique is necessary
> to prevent the topmost class from trying to call that method on object
> and erroring out.

But in that case the Blocker wouldn't call super since it is acting as the base class.

--
~Ethan~