[Python-ideas] ABC: what about the method arguments ?

[Georg Brandl]

Am 23.09.2010 16:37, schrieb Tarek Ziadé:
> Hello,
> 
> ABC __subclasshook__ implementations will only check that the method
> is present in the class. That's the case for example in
> collections.Container. It will check that the __contains__ method is
> present but that's it. It won't check that the method has only one
> argument. e.g. __contains__(self, x)
> 
> The problem is that the implemented method could have a different list
> of arguments and will eventually fail.

I'm not concerned about this in the least.  Whoever implements a special
method with the wrong signature has more pressing problems than a false-
positive ABC subclass check.  And AFAIK, our ABCs only check for special
methods.

> Using inspect, we could check in __subclasshook__ that the arguments
> defined are the same than the ones defined in the abstractmethod.--
> the name and the ordering.

"ordering"?

Georg


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