[Python-Dev] ABC issues

[Raymond Hettinger]

>>> * The 2.6-backported Mapping ABC has the 3.0 dict API,
>>>  that is, it uses keys() that returns a view etc.
>>
>> Curious to hear what Guido thinks about this one.
>> A nice use of the Mapping ABC is to be able to
>> get 3.0 behaviors.  I thought that was the whole
>> point of all these backports.  If the ABC gets altered,
>> then it just makes the 2-to-3 conversion harder.
> 
> It's wrong if the ABC doesn't describe the behavior of actual
> implementations; that is its primary purpose, the mixin class is a
> nice side benefit.

ISTM, the one purpose of backporting is to make 2.6 closer to 3.0.  
Altering the API will just make them further apart.  


Raymond