From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Original-To: caml-list@yquem.inria.fr Delivered-To: caml-list@yquem.inria.fr Received: from concorde.inria.fr (concorde.inria.fr [192.93.2.39]) by yquem.inria.fr (Postfix) with ESMTP id BC102BB84 for ; Wed, 10 May 2006 20:16:17 +0200 (CEST) Received: from pauillac.inria.fr (pauillac.inria.fr [128.93.11.35]) by concorde.inria.fr (8.13.0/8.13.0) with ESMTP id k4AIGGQu015005 for ; Wed, 10 May 2006 20:16:17 +0200 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 UAA23724 for ; Wed, 10 May 2006 20:16:16 +0200 (MET DST) Received: from lion.seas.upenn.edu (LION.SEAS.upenn.edu [158.130.12.194]) by concorde.inria.fr (8.13.0/8.13.0) with ESMTP id k4AIGFSQ015000 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Wed, 10 May 2006 20:16:16 +0200 Received: from [192.168.19.128] (LVN514-2.cis.upenn.edu [158.130.50.247]) (authenticated bits=0) by lion.seas.upenn.edu (8.13.6/8.12.10) with ESMTP id k4AIGBnU021396 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NOT); Wed, 10 May 2006 14:16:12 -0400 Message-ID: <44622DD5.7050304@cis.upenn.edu> Date: Wed, 10 May 2006 14:15:49 -0400 From: Geoffrey Alan Washburn User-Agent: Thunderbird 1.5.0.2 (X11/20060420) MIME-Version: 1.0 Newsgroups: gmane.comp.lang.caml.inria To: Dan Grossman Cc: caml-list@inria.fr Subject: Re: OO design References: <53c655920605050235k64e70333je8df813239ea3c53@mail.gmail.com> <20060508.121743.65190532.garrigue@math.nagoya-u.ac.jp> <200605082329.36911.David.Teller@ens-lyon.org> <445FB9C7.4040703@cs.washington.edu> <446152CB.5010605@cis.upenn.edu> <44621204.4020601@cs.washington.edu> In-Reply-To: <44621204.4020601@cs.washington.edu> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Miltered: at concorde with ID 44622DF1.000 by Joe's j-chkmail (http://j-chkmail.ensmp.fr)! X-Miltered: at concorde with ID 44622DEF.000 by Joe's j-chkmail (http://j-chkmail.ensmp.fr)! X-Spam: no; 0.00; upenn:01 enforces:01 monadic:01 wrote:01 writes:01 alan:01 latter:03 raises:05 reads:06 cis:07 rather:07 okay:07 approach:07 protocols:08 edu:08 X-Spam-Checker-Version: SpamAssassin 3.0.3 (2005-04-27) on yquem.inria.fr X-Spam-Level: X-Spam-Status: No, score=0.0 required=5.0 tests=none autolearn=disabled version=3.0.3 Dan Grossman wrote: > It enforces that you don't confuse your reads and writes, but *not* that > you don't use a file after you close it. A monadic approach (where each > operation would return a "new" file) or linearity appears necessary for > the latter. Okay, good point. However, that raises the interesting question of whether there is a nice positive specification of the class of "protocols" that are expressible in the presence of effects, rather than a negative characterization -- all those that can be broken by aliasing, nontermination, etc.