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 GAA25051; Fri, 6 Sep 2002 06:16:10 +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 GAA25044 for <caml-list@pauillac.inria.fr>; Fri, 6 Sep 2002 06:16:10 +0200 (MET DST)
Received: from corwin.mutu.net (mutu.net [80.65.226.162])
	by nez-perce.inria.fr (8.11.1/8.11.1) with ESMTP id g864G9911770
	for <caml-list@inria.fr>; Fri, 6 Sep 2002 06:16:09 +0200 (MET DST)
Received: by corwin.mutu.net (Postfix, from userid 1000)
	id 62753159025; Fri,  6 Sep 2002 06:16:08 +0200 (CEST)
To: caml-list@inria.fr
Subject: [Caml-list] strange typing errors
X-face: '|!UPdE>Ot'L}nt?<v%6-sA)\t%sB-h!iq+qnL+WDXuk,WCL'eS)Y.O'cqRc)7Ka?!HZm1jk+(g~G->6Tf|'s{y%l~,+Yc5|p8A}ibew|_!vc48pPNPPx@7QA~$`$g=|yH*8sh9R]Xj1(CV7oUe>#/,t.(Z4F
From: Dimitri Ara <dimitri@nerim.net>
Date: 06 Sep 2002 06:16:08 +0200
Message-ID: <874rd3wy5z.fsf@corwin.mutu.net>
User-Agent: Gnus/5.0808 (Gnus v5.8.8) Emacs/21.1
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Sender: owner-caml-list@pauillac.inria.fr
Precedence: bulk

        Hi,

While ICFPing, I came upon some strange typing error messages.

The first one is :

class type ct = object
  method m : l:int -> ct
end

let rec f (o : ct) =
  let rec g o =
    let x = o#m 1 in
      g x in
    g o

which is well typed accorded to caml if I remove the l label. Here is
the error I got:

This expression has type ct = < m : l:int -> ct > as 'a
but is here used with type 'a

The second one is ill-typed and get the same error message:

class type ct = object
  method m : l:int -> int
end

let rec f (o : ct) =
  let rec g o =
    let x = o#m 1 in
      g x in
    g o

If I remove the label I got a stranger error:

This expression has type ct = < m : int -> int > as 'a
but is here used with type 'a
Type int is not compatible with type ct = 'a 

Can someone explain that?

-- 
Dimitri Ara
-------------------
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