Is this Pythonic?

[Reinhold Birkenfeld]

Delaney, Timothy (Tim) wrote:
> Peter Hansen wrote:
> 
>> Change those to "raise NotImplementedError('blah')" instead and you'll
>> be taking the more idiomatic approach.
> 
> One thing I've noticed, which I may raise on python-dev ...
> NotImplementedError does *not* play well with super() ...
> 
> class A (object):
>     def test (self):
>         raise NotImplementedError
> 
> class B (object):
>     def test (self):
>         print 'B'
>         super(B, self).test()
> 
> class C (B, A):
>     def test (self):
>         print 'C'
>         super(C, self).test()
> 
> It's actually worse than AttributeError, because the method actually
> exists. In both cases though you need to know when you create the base
> class how it's going to be used to work out whether a super() call is
> needed.
> 
> One option is to do a try: except (AttributeError, NotImplementedError).
> Yuk - talk about hiding errors :(

Hm... one could return NotImplemented from the abstract method. It won't raise
an error immediately, but will certainly be discovered at some point.

Not optimal though.

Reinhold