Object en ocaml
===============

::


    utop # let myPt =
         object
           val mutable x = 0
           val mutable y = 0
           method get_x = x
           method get_y = y
           method setcoord new_x new_y = x <- new_x ; y<- new_y
         end;;
    val myPt : < get_x : int; get_y : int; setcoord : int -> int -> unit > = <obj>                                                                                               ─( 17:23:21 )─< command 1 >───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────{ counter: 0 }─utop # myPt#get_x ;;
    - : int = 0                                                                                                                                                                  ─( 17:23:24 )─< command 2 >───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────{ counter: 0 }─utop # myPt#setcoord 5 89 ;;
    - : unit = ()                                                                                                                                                                ─( 17:23:45 )─< command 3 >───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────{ counter: 0 }─utop # myPt#get_y
    ;;
    - : int = 89


classe point
------------

::


    (*  ocamlg points.cmo pointClass.ml *)
    open Graphics ;;
    open Points ;;
    open_graph " ";;
    set_line_width 5 ;;
    set_color magenta ;;

    set_window_title "points" ;;

    let p1 = new point (0,0)
    let p2 = new point (3,4) ;;
    p1#lineto (10,28) ;;
    p1#lineto (222,55) ;;
    print_string (p1#to_string ()) ;;
    print_newline () ;;

    p1#lineto (50, 125) ;;

    ignore (read_key () ) ;;
    close_graph () ;;

::


    (* l'objet point comme la possibilite de lier
    la representation et le dessin sur le graphe
    *)
    (* ocamlc graphics.cma points.ml *)
    class point (x_init,y_init) =
       object
         val mutable x = x_init
         val mutable y = y_init
         method get_x = x
         method get_y = y
         method moveto (a,b) =  x <- a ; y <- b
         method rmoveto (dx,dy) =  x <- x + dx ; y <- y + dy
         method lineto (a, b) = Graphics.lineto a b ; x <- a ; y <- b
         method to_string () =
             "( " ^ (string_of_int x) ^ ", " ^ (string_of_int y) ^")"
         method distance () = sqrt (float(x*x + y*y))
       end ;;

    (*
    let p1 = new point (0,0)
    let p2 = new point (3,4) ;;
    p1#get_x;;
    p2#get_y;;
    p1#to_string();;
    p1#moveto (1,2) ;;
    p1#rmoveto (2,5) ;;
    p1#to_string () ;;
    *)

    (* point avec un record

    type color = Rouge | Vert | Bleu
    type point = {x:int; c:color}

    class point (x_init, y_init) =
       object
         val x = x_init
         val y = y_init
         method get_x = x
         method get_y = y
         (* a faire avec le self *)
         method moveto (point:p) =  point(p.get_a,p.get_b)
         method rmoveto (point:p) =  point(x + dx, y + dy)
         method to_string () =
             "( " ^ (string_of_int x) ^ ", " ^ (string_of_int y) ^")"
         method distance () = sqrt (float(x*x + y*y))
       end ;;

    let p1 = new point (0, 0);;
    let p2 = new point (3, 4);;
    (*
    p1#get_x;;
    p2#get_y;;
    p1#to_string();;
    *)