From mboxrd@z Thu Jan 1 00:00:00 1970 X-Sympa-To: caml-list@inria.fr Received: from mail4-relais-sop.national.inria.fr (mail4-relais-sop.national.inria.fr [192.134.164.105]) by walapai.inria.fr (8.13.6/8.13.6) with ESMTP id q0CAjwOe031403 for ; Thu, 12 Jan 2012 11:45:58 +0100 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AtYAAAq5Dk+K57AEmWdsb2JhbABDhQ6lRYIzIgEBAQEBCAsLBxQlgXIBAQUjDwEFQBELGgIFFgsCAgkDAgECAUUTCAKuIpE3gS+HUoIGgRYEml6MbA X-IronPort-AV: E=Sophos;i="4.71,497,1320620400"; d="scan'208";a="126568143" Received: from ariane.ens-cachan.fr ([138.231.176.4]) by mail4-smtp-sop.national.inria.fr with ESMTP/TLS/ADH-AES256-SHA; 12 Jan 2012 11:45:53 +0100 Received: from localhost (localhost [127.0.0.1]) by ariane.ens-cachan.fr (Postfix) with ESMTP id EF81DBCB76 for ; Thu, 12 Jan 2012 11:45:52 +0100 (CET) X-Virus-Scanned: Debian amavisd-new at ens-cachan.fr Received: from ariane.ens-cachan.fr ([127.0.0.1]) by localhost (ariane.ens-cachan.fr [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id ebHv3CoV-8lD for ; Thu, 12 Jan 2012 11:45:52 +0100 (CET) Received: from olive.lsv.ens-cachan.fr (olive.lsv.ens-cachan.fr [138.231.81.248]) by ariane.ens-cachan.fr (Postfix) with ESMTP id B7BCCBD154 for ; Thu, 12 Jan 2012 11:45:52 +0100 (CET) Received: from [138.231.81.43] (unknown [138.231.81.43]) by olive.lsv.ens-cachan.fr (Postfix) with ESMTP id B042A4C01B5 for ; Thu, 12 Jan 2012 11:45:52 +0100 (CET) Message-ID: <4F0EBA0F.1080400@lsv.ens-cachan.fr> Date: Thu, 12 Jan 2012 11:46:39 +0100 From: Romain Bardou User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.24) Gecko/20111114 Icedove/3.1.16 MIME-Version: 1.0 To: caml-list@inria.fr References: <1326209342.96423.YahooMailNeo@web111502.mail.gq1.yahoo.com> <1326214824.62249.YahooMailNeo@web111507.mail.gq1.yahoo.com> <4F0D6913.4090207@wp.pl> <4F0D87E8.90602@wp.pl> <13b032314ec2f8f50916bcfa6eb7f72b.squirrel@mail.mpi-sws.org> <4F0D9501.60107@wp.pl> <869af1b432cfe71214ce68625a92a1c0.squirrel@mail.mpi-sws.org> <4F0EADF6.10309@wp.pl> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Validation-by: bardou@lsv.ens-cachan.fr Subject: Re: [Caml-list] Re: References and polymorphism Le 12/01/2012 11:05, Andrej Bauer a écrit : > I would just like to remind the participants of this discussion that > the value restriction historically originated as a _simplifaction_ of > fancier and more capable forms of parametric polymorphism. The older, > more capable kinds of ML polymorphism grew increasingly more complex, > until Andrew Wright actually looked at what sort of programs people > wrote and noticed that for the most part the fancy stuff was not > needed. Thus it was decided that the ML polymorphism be _simplified_. > This was a good decision, as it made types easier to understand and > easier to implement, at a miniscule cost. > > That is, we know that value restriction can be "improved", but by > trying to do so you are just repeating the mistakes that were alerady > made in the 90's. > > With kind regards, > > Andrej > Some even argue, using the same kind of arguments, that (local) let should not be generalized [1]. Here we are not talking about local values though. [1] Dimitrios Vytiniotis, Simon Peyton Jones and Tom Schrijvers, Let Should Not Be Generalised -- Romain Bardou