[ruby-talk:14266] how change instances class

Sorry, din't find it in pickaxe:

(1) How(if possible) can I change the value of the class attribute?

Say, that a instance at first is known as belonging to a fairly general
class, and when we gather more information, it turns out to belong more
precisely to a subclass.

Is this part of Ruby 'as is', or do I have to extend. Point is to keep
instance id, while the knowledge of which class it belongs to changes. Just
like in real world as reflected in human language. (Changing to a subclass
might be readily accepted, while changing to an unrelated class would demand
an admittance that the first guess was an error.)

(2) How do I delete (un-mix) a mixin?

Thanks for any helpful comments/pointers.

amike via Henning