Why do descriptors (and thus properties) only work on attributes.

[Diez B. Roggisch]

Antoon Pardon wrote:

> Op 2005-02-28, Paul Rubin schreef <http>:
>> Antoon Pardon <apardon at forel.vub.ac.be> writes:
>>> Can anyone explain why descriptors only work when they are an attribute
>>> to an object or class.  I think a lot of interesting things one can
>>> do with descriptors would be just as interesting if the object stood
>>> on itself instead of being an attribute to an other object.
>>
>> How would that work?
> 
> Well AFAIU a descriptor is an object with at least one method out of
> __get__, __set__ or __del__. I don see why implicitly calling one
> of these methods would be any more difficult when they are autonomous
> objects than when they are attributes.

I still don't see how that is supposed to work for "a lot of interesting
things". Can you provide examples for one of these interesting things?

-- 
Regards,

Diez B. Roggisch