]> Jacques Garrigue wrote: > > Sorry, but there is no handling of instanciation via subtyping. > Currently subtyping and instanciation are orthogonal concepts: you > cannot subtype in an .mli, and you cannot instanciate an > explicitly polymorphic type when subtyping. > I believe it's correct, but you won't make me write the code without a > proof :-) That is really an interesting comment. I wonder, what are people currently researching w.r.t. the object-oriented features of O'Caml? Besides the above, Jacques said that recursive types with classes is not completely defined because (paraphrasing) recursive types are polymorphic and recursive classes are monomorphic: type variant = Node of node and class node = object method as_variant : variant = Node self end I wonder, does a similar problem apply to recursive exceptions and classes?: (* email me for a complete example *) exception NotFound of node and class node = object method find x = ... else raise (NotFound self) end;; And, similarly, it does seem odd that currently it is impossible to create a polymorphic method equivalent to "map" (This type of problem is mentioned in http://citeseer.nj.nec.com/remy98objective.html). Besides polymorphism, I wonder if it is possible to add open classes and multiple dispatch to O'Caml like MultiJava does for Java (http://www.cs.iastate.edu/~cclifton/multijava/). I'm just a beginner and I don't know any of the theory of this yet, so i'm hoping somebody else will give Jacques some proofs of solutions to the above :) Thanks, Brian ------------------- To unsubscribe, mail caml-list-request@inria.fr Archives: http://caml.inria.fr Bug reports: http://caml.inria.fr/bin/caml-bugs FAQ: http://caml.inria.fr/FAQ/ Beginner's list: http://groups.yahoo.com/group/ocaml_beginners