Hi, I miss a convenient way to ask a class, if it is a subclass of a given superclass (like is_a?, kind_of? for instances). I wish I could type something like: Integer.is_superclass?(Fixnum) Is there a possiblity, I did not know to achieve this? Best regards, Matthias _________________________________________________________ Do You Yahoo!? Get your free @yahoo.com address at http://mail.yahoo.com