From mboxrd@z Thu Jan  1 00:00:00 1970
Received: (from majordomo@localhost) by pauillac.inria.fr (8.7.6/8.7.3) id FAA21034; Thu, 26 Aug 2004 05:22:37 +0200 (MET DST)
X-Authentication-Warning: pauillac.inria.fr: majordomo set sender to owner-caml-list@pauillac.inria.fr using -f
Received: from nez-perce.inria.fr (nez-perce.inria.fr [192.93.2.78]) by pauillac.inria.fr (8.7.6/8.7.3) with ESMTP id FAA21662 for <caml-list@pauillac.inria.fr>; Thu, 26 Aug 2004 05:22:36 +0200 (MET DST)
From: briand@aracnet.com
Received: from jade.spiritone.com (jade.spiritone.com [216.99.193.136])
	by nez-perce.inria.fr (8.13.0/8.13.0) with ESMTP id i7Q3MY5D007459
	(version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO)
	for <caml-list@pauillac.inria.fr>; Thu, 26 Aug 2004 05:22:35 +0200
Received: from soggy.deldotd.com (216-99-206-32.cust.aracnet.com [216.99.206.32])
	by jade.spiritone.com (8.12.8/8.12.8) with ESMTP id i7Q3MXoR027318
	for <caml-list@pauillac.inria.fr>; Wed, 25 Aug 2004 20:22:33 -0700
Received: from briand by soggy.deldotd.com with local (Exim 3.36 #1 (Debian))
	id 1C0AqP-0000MV-00
	for <caml-list@pauillac.inria.fr>; Wed, 25 Aug 2004 20:22:33 -0700
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
Message-ID: <16685.22393.76718.150882@soggy.deldotd.com>
Date: Wed, 25 Aug 2004 20:22:33 -0700
To: caml-list@pauillac.inria.fr
Subject: [Caml-list] baffled by semicolon
X-Mailer: VM 6.92 under Emacs 21.2.1
X-Miltered: at nez-perce with ID 412D577A.000 by Joe's j-chkmail (http://j-chkmail.ensmp.fr)!
X-Loop: caml-list@inria.fr
X-Spam: no; 0.00; baffled:01 semicolon:01 lablgtk:01 gwindow:01 gmisc:01 semicolon:01 ocaml:01 width:98 height:98 syntax:02 unit:03 obj:03 let:04 let:04 gdk:04 
Sender: owner-caml-list@pauillac.inria.fr
Precedence: bulk


This might really by a lablgtk2 question, but I thought it's probably
more of a ocaml syntax question :

The following works :


let window = GWindow.window ~width:400 ~height:400()
;;

let area = GMisc.drawing_area ~packing:window#add ()
;;

let w = area#misc#realize ()
;

  area#misc#window;;

let drawing = new GDraw.drawable w
;;

However making the simple change

let w = area#misc#realize ()
;;

^^ notice the double semicolon gives an error:
This expression has type unit but is here used with type
  [> `drawable ] Gobject.obj

For the simple reason that w has somehow, mysteriously, become = ()
instead of Gdk.window which is the value it would acquire if it was
only a single semi-colon.

I went back through the manual and really couldn't find anything which
explained the difference between ; and ;; - so it's not at all obvious
to me what's going on here.  I would think that w would take on the value of evaluating 

 area#misc#realize ()

in either case.

???

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