DouKaku?

let decomment s = 
  Stream.iter (fun item ->
    print_string 
      (match item with
      | Kwd s | Ident s -> s
      | String s -> Printf.sprintf "\"%s\"" (String.escaped s)
      | Char c -> Printf.sprintf "'%s'" (Char.escaped c)
      | Int n -> string_of_int n
      | Float f -> string_of_float f
      ); print_char ' '
    ) (make_lexer [] (Stream.of_string s));;

(* decomment "aa\"(* bb \\\" cc *)\"dd '\\\\' (* zz *) ";; *)