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* [Caml-list] Problem with classes or i need help
@ 2003-02-05 21:40 inv2002
  2003-02-05 16:31 ` [Caml-list] Ugly fonts in ocamlbrowser/editor Wai-Sun Chia
  2003-02-06  0:44 ` [Caml-list] Problem with classes or i need help Jacques Garrigue
  0 siblings, 2 replies; 7+ messages in thread
From: inv2002 @ 2003-02-05 21:40 UTC (permalink / raw)
  To: caml-list

I don't know correct solution of my problem.

Here my example:
---begin 1.ml---
#!/usr/bin/env ocamltop

class virtual figure () =
  object
    method virtual to_string: string
  end

class triangle () =
  object
    inherit figure ()
    method private to_string = "Triangle"
    method m1 = Random.float 5.0
  end

class circle () =
  object
    inherit figure ()
    method private to_string = "Circle"
    method m2 = Random.int 6
  end

class screen () =
  object
    val mutable figures = []
    method add_figure f =
      figures <- (f#to_string ) :: figures
  end

let main () =
  let s1 = new screen () in 
  s1#add_figure (new circle ());
  s1#add_figure (new triangle ())

let () = main ()

--end---
[inv@localhost ~]$ ./1.ml
File "./1.ml", line 22, characters 5-121:
Some type variables are unbound in this type:
  class screen :
    unit ->
    object
      val mutable figures : 'a list
      method add_figure : < to_string : 'a; .. > -> unit
    end
The method add_figure has type < to_string : 'a; .. > -> unit where ..
is unbound

I understand the problem, but i don't know solution, help, please.
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^ permalink raw reply	[flat|nested] 7+ messages in thread
end of thread, other threads:[~2003-02-17  8:01 UTC | newest]

Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2003-02-05 21:40 [Caml-list] Problem with classes or i need help inv2002
2003-02-05 16:31 ` [Caml-list] Ugly fonts in ocamlbrowser/editor Wai-Sun Chia
2003-02-06  6:35   ` Jacques Garrigue
2003-02-06  8:31     ` Wai-Sun Chia
2003-02-06  0:44 ` [Caml-list] Problem with classes or i need help Jacques Garrigue
2003-02-14 15:33   ` inv2002
2003-02-15  7:02     ` Jacques Garrigue

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