[Python-3000] pep 3124 plans

[Guido van Rossum]

On 7/19/07, Joe Smith <unknown_kev_cat at hotmail.com> wrote:
> So the state of the PEP? From the rest of the posts so far,
> it sounds like there is no real objection to the basic end user API as
> described in the PEP,

Actually I want to reserve judgment on that until the PEP is rewritten
to explain and document the underlying mechanisms. It is currently
impossible (for me, anyway) to understand how the machinery to support
the described features could be built. Without that I cannot approve
the PEP. Phillip knows this but is too busy to work on it.

> except for the case of retroactive generification, which GvR wants made
> explict in the user's code, AIUI.
>
> But there are concerns about the implementation. Overiding inside classes
> would need a new implementation, but at the moment your not sure how to
> implement that. Also your current bootstrapping system requires in-place
> modifing of some functions. You think using a third type of function could
> perhaps fix that if no cleaner solution appears, correct?
>
> Also what has happened with the Interfaces/Adpatation/Aspects part of the
> document? How does that mesh with the ABC's?
> After all adaptable interfaces and ABCs have such similar use cases users
> may not be sure which to use.
> Or has that part been defered for now, as the GF and method combination part
> is not dependent on those?

AFAIK Phillip has declared that his implementation only uses (or could
be made to only use) isinstance()/issubclass(), and the overriding of
these two used by the ABCs is actually very convenient for the GF PEP.

-- 
--Guido van Rossum (home page: http://www.python.org/~guido/)