[Python-Dev] PEP 246 - concrete assistance to developers of new adapter classes

[Alex Martelli]

On 2005 Jan 21, at 14:02, Nick Coghlan wrote:

> Phillip's monkey-typing PEP (and his goal of making it easy to write 
> well behaved adapters) got me wondering about the benefits of 
> providing an adaptation. Adapter class that could be used to reduce 
> the boiler plate required when developing new adapters. Inheriting 
> from it wouldn't be *required* in any way - doing so would simply make 
> it easier to write a good adapter by eliminating or simplifying some 
> of the required code. Being written in Python, it could also serve as 
> good documentation of recommended adapter behaviour.
>
> For instance, it could by default preserve a reference to the original 
> object and use that for any further adaptation requests:
>
> class Adapter(object):
>   def __init__(self, original):
>     self.original = original
>
>   def __conform__(self, protocol):
>     return adapt(self.original, protocol)
>
> Does anyone else (particularly those with PEAK and Zope interface 
> experience) think such a class would be beneficial in encouraging good 
> practices?

Yes, there was something just like that in Nevow (pre-move to the zope 
interfaces) and it sure didn't hurt.


Alex