[Python-ideas] The Descriptor Protocol...

[Martin Chilvers]

Hi Raymond,

Thanks for your replies. We currently use the traditional 
__getattribute__ hook, and the original question came up as part of a 
debate about the various merits of descriptors vs __getattribute__.

Martin

On 02/03/2011 19:35, Raymond Hettinger wrote:
> P.S.  Python is very customizable.  The descriptor protocol in
> implemented by __getattribute__, so it's not a hard exercise to write
> your own __getattribute__ to implement your own variant of the
> descriptor protocol.  Here's a quick and dirty example:
>
> class Str: 'Descriptor using a custom protocol' def __my_get__(self,
> obj, key): print(key * 5) return obj
>
> class A:
>
> @property        # old protocol def x(self): return 10
>
> y = Str()        # new protocol
>
> def __getattribute__(self, key): 'Implement an alternative descriptor
> protocol' attr = object.__getattribute__(self, key) if hasattr(attr,
> '__my_get__'): return attr.__my_get__(attr, key) return attr
>
> a = A() print(a.x) print(a.y)
>
>