why are people still using classic classes?

Steve Holden steve at holdenweb.com
Fri Jan 14 22:51:44 CET 2005


Peter Hansen wrote:

> Paul Rubin wrote:
> 
>> Simon Wittber <simonwittber at gmail.com> writes:
>>
>>>> Is there a reason NOT to use them?  If a classic class works fine, what
>>>> incentive is there to switch to new style classes?  
>>>
>>>
>>> Perhaps classic classes will eventually disappear?
>>
>>
>> It just means that the formerly "classic" syntax will define a
>> new-style class.  Try to write code that works either way.
> 
> 
> Unfortunately, if we should follow the recent advice about
> always using "super()" in the __init__ method, it's hard
> to do what you suggest (though it sounds like good advice)
> without resorting to extreme ugliness:
> 
>  >>> class Classic:
> ....   def __init__(self):
> ....     super(Classic, self).__init__()
> ....
>  >>> c = Classic()
> Traceback (most recent call last):
>   File "<stdin>", line 1, in ?
>   File "<stdin>", line 3, in __init__
> TypeError: super() argument 1 must be type, not classobj
> 
> Could classic classes ever be removed without us having manually
> to fix all __init__ calls to the superclass?
> 
That's not really an issue unless there's a diamond-shaped inheritance 
graph and linearisation of the the super classes is required to ensure 
that things stay sane. Remembering that the MO for classic classes and 
types are rather different, how many cases do you think it will matter?

regards
  Steve
-- 
Steve Holden               http://www.holdenweb.com/
Python Web Programming  http://pydish.holdenweb.com/
Holden Web LLC      +1 703 861 4237  +1 800 494 3119



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