(* do-it-yourself objects using references *)

type obj =
       {get   : unit -> int;
        inc   : unit -> unit;
        reset : unit -> unit}

(* val make : unit -> obj *)

let make() =
      let r = ref 0
      in {get   = (function () -> !r);
          inc   = (function () -> r := !r + 1);
          reset = (function () -> r := 0)}

(*
   try

     let x = make();;
     x.get();;
     x.inc();;
     x.inc();;
     x.get();;
     x.reset();;
     x.get();;

*)