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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Tue, 25 Jun 2013 11:44:48 -0600
Subject: Re: What is the semantics meaning of 'object'?
To: Python <python-list@python.org>
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On Sun, Jun 23, 2013 at 1:33 PM, Antoon Pardon
<antoon.pardon@rece.vub.ac.be> wrote:
> Op 23-06-13 18:35, Steven D'Aprano schreef:
>> Please don't. This is false economy. The time you save will be trivial,
>> the overhead of inheritance is not going to be the bottleneck in your
>> code, and by ignoring super, you only accomplish one thing:
>>
>> - if you use your class in multiple inheritance, it will be buggy.
>
>
> Which is why I don't understand that the python standard library still
> contains that kind of code. At least it did in 3.2 and I saw nothing
> in the 3.3 release notes that would make me suspect this has changed.

This bothers me as well.  If you look at Raymond Hettinger's "super()
considered super" article, he includes the (correct) advice that
super() needs to be used at every level of the call chain.  At the end
of the article, he offers this example to show how "easy" multiple
inheritance can be:

from collections import Counter, OrderedDict

class OrderedCounter(Counter, OrderedDict):
     'Counter that remembers the order elements are first seen'
     def __repr__(self):
         return '%s(%r)' % (self.__class__.__name__,
                            OrderedDict(self))
     def __reduce__(self):
         return self.__class__, (OrderedDict(self),)

oc = OrderedCounter('abracadabra')

Which is pretty cool in its simplicity, but here's the rub (which I
have previously noted on this list): OrderedDict doesn't use super.
Counter does, but not cooperatively; it just calls super().__init__()
with no arguments.  So the fact that this example works at all is
basically luck.