On 04.03.2010, at 21:42, Michael Haupt wrote:
> 
> Stéphane,
> 
> 2010/3/4 Stéphane Rollandin <lecteur at zogotounga.net>:
>> If #is: implementation has to reflect a class hierarchy, then I don't see
>> how it can be any better than #isKindOf: and #isMemberOf:
> 
> #isKindOf: accepts a Class, while #is: accepts a Symbol. Helps decoupling.

Agreed, though that should be separate from #is: which had the idea of being about protocols, not class membership/inheritance. 

How about having both:

#isA: will take a class name symbol, implementation like Andreas proposed based on #isKindOf:

#is: will take a symbol not directly related to a class, implemented and used as in Cuis

- Bert -