I just got from LISP to OCaml, and wondered if there is an equivalent of
generic functions from LISP (CLOS) in OCaml. In the Common Lisp Object
System methods don't belong to certain objects/classes. They are just
function specializing on the argument types. So basically I want to
write something like:

let foo (x : int) = x*x;;
let foo (x : float) = x*.x;;

This, obviously, will not work since foo is just redefined by the second
statement. One would think, that having methods not being belonging to
objects/classes, is rather pointless. Well 95% of the time, there is no
necessity for that. But in the other 5%, it is really helpful.