dispatching methods on a class type

[taarna!kaveh%comback.UUCP@IRO.UMontreal.CA (Kaveh Kardan)]

I am wondering if there is a way in clos of dispatching methods on a class
itself, as opposed to instances of the class.

Here's the scenario:

I have a complex hierarchical data structure, and would like to be able to
extract all elements of a given class from it.  I have a method for each
class which goes through the data structure and returns a list of the found
instances of the class.  When I want a list off all instances of class
'foo', I can't just call the method for foo, since I have no instances of
foo handy.

Thanks,

Kaveh

Kaveh Kardan                                  Systeme Taarna
kaveh@taarna.UUCP                             Montreal, Quebec, Canada
uunet.uu.net!taarna!kaveh                     (514)844-8448