Re: dia2code objc

[Nicola Pero]

> > you can check the object's inheritance with NSObject's -isKindOfClass:
> > method, which will check if an object is either an instance of a class, or
> > a decendant of it.  you could do somthing as simple as loop over a list of
> > classes that are permissable.
> 
> unless the caller is passed as a parameter, it would be hard to find out who 
> sent a message i suppose?

yes - I don't think I read all the discussion, but if you're building a
proxy which only allows some messages to what it's proxying, you always
filter basing on the class of the receiver -- unless of course the sender
is an argument as in (gui) actions.

in general terms, there is nothing as the 'sender' - the method could be
called in a function (where no 'sender' is defined), so having a different
behaviour depending on the 'sender' is an undefined notion.