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 RAA13354; Thu, 29 Jan 2004 17:20:55 +0100 (MET) X-Authentication-Warning: pauillac.inria.fr: majordomo set sender to owner-caml-list@pauillac.inria.fr using -f Received: from concorde.inria.fr (concorde.inria.fr [192.93.2.39]) by pauillac.inria.fr (8.7.6/8.7.3) with ESMTP id RAA13000 for ; Thu, 29 Jan 2004 17:20:54 +0100 (MET) Received: from nexus.stwing.upenn.edu (NEXUS.STWING.UPENN.EDU [165.123.132.61]) by concorde.inria.fr (8.11.1/8.11.1) with ESMTP id i0TGKqP11546 for ; Thu, 29 Jan 2004 17:20:53 +0100 (MET) Received: from force.stwing.upenn.edu (root@force.stwing.upenn.edu [165.123.132.65]) by nexus.stwing.upenn.edu (8.12.10/8.12.9) with ESMTP id i0TGKpiV013128 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Thu, 29 Jan 2004 11:20:51 -0500 (EST) Received: from force.stwing.upenn.edu (wlovas@localhost [127.0.0.1]) by force.stwing.upenn.edu (8.12.10/8.12.9) with ESMTP id i0TGKoLN029572 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Thu, 29 Jan 2004 11:20:50 -0500 (EST) Received: (from wlovas@localhost) by force.stwing.upenn.edu (8.12.10/8.12.9/Submit) id i0TGKobE029571 for caml-list@inria.fr; Thu, 29 Jan 2004 11:20:50 -0500 (EST) Date: Thu, 29 Jan 2004 11:20:49 -0500 From: William Lovas To: caml-list@inria.fr Subject: fancy types (was Re: [Caml-list] ocaml killer) Message-ID: <20040129162048.GA29094@force.stwing.upenn.edu> Mail-Followup-To: caml-list@inria.fr References: <20040127063230.GA12482@inv_machine> <200401282326.i0SNQntl004612@bismarck-chet.watson.ibm.com> <40184A2F.6040007@dcs.qmul.ac.uk> <200401290000.i0T00ntl006988@bismarck-chet.watson.ibm.com> <40184FB9.4000808@dcs.qmul.ac.uk> <200401290034.i0T0Yutl009000@bismarck-chet.watson.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.4i X-Loop: caml-list@inria.fr X-Spam: no; 0.00; lovas:01 wlovas:01 stwing:01 caml-list:01 2004:99 chet:01 murthy:01 ffi:01 ocaml:01 caml:01 caml:01 exists:01 mainstream:01 discouraged:03 complex:03 Sender: owner-caml-list@pauillac.inria.fr Precedence: bulk On Thu, Jan 29, 2004 at 09:52:31AM +0100, Thomas Fischbacher wrote: > On Wed, 28 Jan 2004, Chet Murthy wrote: > > > These are the things that matter in a language. The fact that CAML > > has fancy types, well, -I- like it, but it isn't why I wrote some of > > my most complex systems in it, and it will never be enough to push > > CAML into the mainstream. > > At least, it is nice to be able to use the FFI to define a function > believe_me: 'a -> 'b which is just the identity, so that one can pass as > an argument a function to itself. There _are_ some situations where things > are best handled by using the fixed-point principle at a deep level. I've passed functions to themselves before without ever having to make use of such a function (which already exists in the standard library, it being mysteriously named Obj.magic and its use being highly discouraged). In all of my scenarios, regular old parametric polymorphism was able to handle the typing. In what sort of situation have you needed this identity function? William ------------------- 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