From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on yquem.inria.fr X-Spam-Level: X-Spam-Status: No, score=0.4 required=5.0 tests=AWL,DNS_FROM_RFC_ABUSE autolearn=disabled version=3.1.3 X-Original-To: caml-list@yquem.inria.fr Delivered-To: caml-list@yquem.inria.fr Received: from mail4-relais-sop.national.inria.fr (mail4-relais-sop.national.inria.fr [192.134.164.105]) by yquem.inria.fr (Postfix) with ESMTP id 07736BC6B for ; Tue, 30 Oct 2007 20:03:01 +0100 (CET) X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AgAAAMgcJ0fAXQImh2dsb2JhbACOYQIBCAop X-IronPort-AV: E=Sophos;i="4.21,348,1188770400"; d="scan'208";a="18778243" Received: from discorde.inria.fr ([192.93.2.38]) by mail4-smtp-sop.national.inria.fr with ESMTP; 30 Oct 2007 20:03:00 +0100 Received: from mail3-relais-sop.national.inria.fr (mail3-relais-sop.national.inria.fr [192.134.164.104]) by discorde.inria.fr (8.13.6/8.13.6) with ESMTP id l9UJ2xDe001934 (version=TLSv1/SSLv3 cipher=RC4-SHA bits=128 verify=OK) for ; Tue, 30 Oct 2007 20:03:00 +0100 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AgAAAA4cJ0fZDAs+g2dsb2JhbACOYQIBCAQGEREH X-IronPort-AV: E=Sophos;i="4.21,348,1188770400"; d="scan'208";a="5293774" Received: from smtp008.mail.ukl.yahoo.com ([217.12.11.62]) by mail3-smtp-sop.national.inria.fr with SMTP; 30 Oct 2007 20:02:59 +0100 Received: (qmail 43524 invoked from network); 30 Oct 2007 19:02:58 -0000 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.fr; h=Received:X-YMail-OSG:In-Reply-To:References:Mime-Version:Content-Type:Message-Id:Cc:Content-Transfer-Encoding:From:Subject:Date:To:X-Mailer; b=vUrAugdxFv0B2/dsV35Qrl3MkUpaz9z7h2c0gHOj9WYSS4T4i1xsqNtBqQNpktfRE6Nv+97zHLCZNd6iLaYqz8kHq6+u4pJNwxcAbii3yErwM3Vr1EMiu0BPaGuAGiRdtCgf31AM/ddEI4qTF/utk4/YgcSSCtASgGl7dXnMLi4= ; Received: from unknown (HELO ?192.168.0.11?) (vincent.aravantinos@82.229.199.66 with plain) by smtp008.mail.ukl.yahoo.com with SMTP; 30 Oct 2007 19:02:58 -0000 X-YMail-OSG: i7AA4qgVM1nzAQko6DLJQSBjovwb_jUgzpIL1Fss3CJoS1B5i6LTccz0TgHgdFX9k6r1SIfqag-- In-Reply-To: <1193766983.7594.15.camel@rosella.wigram> References: <1193225773.3612.27.camel@Blefuscu> <471F7F7B.9040905@fmf.uni-lj.si> <666572260710241205x19edbd4ar840811b1d7a7315f@mail.gmail.com> <5i2kv4-hmj.ln1@mantle.rutgers.edu> <47275E10.4070705@janestcapital.com> <47276500.3050501@gmail.com> <1193766983.7594.15.camel@rosella.wigram> Mime-Version: 1.0 (Apple Message framework v752.2) Content-Type: text/plain; charset=ISO-8859-1; delsp=yes; format=flowed Message-Id: <27F204A8-D45A-4CBF-84BB-BB0A23A261CA@yahoo.fr> Cc: Gurus Ocaml Content-Transfer-Encoding: quoted-printable From: Vincent Aravantinos Subject: Re: [Caml-list] Re: Which syntax to teach ? Date: Tue, 30 Oct 2007 20:02:56 +0100 To: skaller X-Mailer: Apple Mail (2.752.2) X-Miltered: at discorde with ID 47277FE3.000 by Joe's j-chkmail (http://j-chkmail . ensmp . fr)! X-Spam: no; 0.00; syntax:01 functors:01 functors:01 functor:01 ocaml:01 functor:01 ocaml:01 edgar:98 wrote:01 wrote:01 caml-list:01 functions:01 structures:02 parameter:02 objects:02 Le 30 oct. 07 =E0 18:56, skaller a =E9crit : > On Tue, 2007-10-30 at 12:08 -0500, Edgar Friendly wrote: >> Brian Hurt wrote: >>> Chung-chieh Shan wrote: >>> >>>> Any tips on how (and perhaps how not) to teach functors? > > The problem teaching functors is that the essential feature > of functors is missing -- a functor is a structure preserving > map but there's no way to specify any structure other than > in comments. Indeed, I don't really see the link between Ocaml functors and =20 Category ones (???). Could someone explain this ? Classically, types would be the objects and functions would be the =20 arrows. But then a functor does not map a type to each original type =20 neither a function to each original function. So what ? Maybe we could see all the module structures associated to a module =20 signature form a category ? And then a (ocaml) functor would indeed =20 be a (category) functor from the category associated to the signature =20= of the parameter to the category of its returned module type. (?) Is this the way to go ? I thing I've read once that it was linked =20 with "institutions" theory (of Goguen), is this right ? Thanks for answers, Vincent=