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=0.0 required=5.0 tests=none 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 96F14BBAF for ; Sat, 12 Jul 2008 09:34:09 +0200 (CEST) X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: ApoEAAv7d0jAXQIm/2dsb2JhbACoeA X-IronPort-AV: E=Sophos;i="4.30,349,1212357600"; d="scan'208";a="27258728" Received: from discorde.inria.fr ([192.93.2.38]) by mail4-smtp-sop.national.inria.fr with ESMTP; 12 Jul 2008 09:34:09 +0200 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 m6C7Y8Zh016950 (version=TLSv1/SSLv3 cipher=RC4-SHA bits=128 verify=OK) for ; Sat, 12 Jul 2008 09:34:08 +0200 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: ApoEAL/7d0iCNhAB/2dsb2JhbACocg X-IronPort-AV: E=Sophos;i="4.30,349,1212357600"; d="scan'208";a="15047960" Received: from kurims.kurims.kyoto-u.ac.jp ([130.54.16.1]) by mail3-smtp-sop.national.inria.fr with ESMTP; 12 Jul 2008 09:34:06 +0200 Received: from localhost (silicon [130.54.16.72]) by kurims.kurims.kyoto-u.ac.jp (8.13.8/8.13.8) with ESMTP id m6C7Y3Tg011068; Sat, 12 Jul 2008 16:34:03 +0900 (JST) Date: Sat, 12 Jul 2008 16:34:03 +0900 (JST) Message-Id: <20080712.163403.68558844.keiko@kurims.kyoto-u.ac.jp> To: jun.furuse@gmail.com Cc: caml-list@inria.fr Subject: Re: [Caml-list] Recursive module and class From: Keiko Nakata In-Reply-To: <87abgqbplw.wl%jun.furuse@gmail.com> References: <87abgqbplw.wl%jun.furuse@gmail.com> X-Mailer: Mew version 4.2 on Emacs 20.7 / Mule 4.1 (AOI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Miltered: at discorde with ID 48785E70.000 by Joe's j-chkmail (http://j-chkmail . ensmp . fr)! X-Spam: no; 0.00; recursive:01 recursive:01 variants:01 checker:01 bug:01 checker:01 polymorphic:01 typing:01 caml-list:01 caml-list:01 define:02 modules:02 modules:02 caml:02 interaction:02 Hello. To the best of my knowledge, there is subtle interaction between typing of recursive modules and unfolding of recursive structural types, i.e, classes and polymorphic variants. I remember Jacques has hit a similar problem: http://caml.inria.fr/pub/ml-archives/caml-list/2008/02/de4c1ddaa8bf3c0ef9350d8fb4f1e8f7.en.html My understanding is that with recursive modules you may define two types that are equivalent but do not join together by simple unfolding of abbreviations; this seems to confuse the type checker. I believe this is a known bug of the current implementation of the type checker. With best regards, Keiko