From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Marius Vollmer Newsgroups: gmane.lisp.guile.user,gmane.lisp.guile.devel Subject: The order of objects returned from a guardian Date: Wed, 27 Jul 2005 02:33:58 +0300 Message-ID: <873bq1gn15.fsf@zagadka.de> NNTP-Posting-Host: main.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: sea.gmane.org 1122421151 5481 80.91.229.2 (26 Jul 2005 23:39:11 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Tue, 26 Jul 2005 23:39:11 +0000 (UTC) Original-X-From: guile-user-bounces+guile-user=m.gmane.org@gnu.org Wed Jul 27 01:39:08 2005 Return-path: Original-Received: from lists.gnu.org ([199.232.76.165]) by ciao.gmane.org with esmtp (Exim 4.43) id 1DxZ0r-0004Ck-RK for guile-user@m.gmane.org; Wed, 27 Jul 2005 01:39:06 +0200 Original-Received: from localhost ([127.0.0.1] helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1DxZ3E-0000Is-HF for guile-user@m.gmane.org; Tue, 26 Jul 2005 19:41:32 -0400 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1DxZ2t-0000Dq-0p for guile-user@gnu.org; Tue, 26 Jul 2005 19:41:12 -0400 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1DxZ2i-00006x-Fi for guile-user@gnu.org; Tue, 26 Jul 2005 19:41:02 -0400 Original-Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1DxZ2g-0008U3-6b for guile-user@gnu.org; Tue, 26 Jul 2005 19:40:58 -0400 Original-Received: from [213.243.153.37] (helo=smtp1.pp.htv.fi) by monty-python.gnu.org with esmtp (Exim 4.34) id 1DxZ6Z-0002gA-Sp for guile-user@gnu.org; Tue, 26 Jul 2005 19:45:00 -0400 Original-Received: from zagadka.ping.de (cs181072157.pp.htv.fi [82.181.72.157]) by smtp1.pp.htv.fi (Postfix) with SMTP id 4C1BD7FC0A for ; Wed, 27 Jul 2005 02:33:46 +0300 (EEST) Original-Received: (qmail 16493 invoked by uid 1000); 26 Jul 2005 23:33:58 -0000 Original-To: guile-user@gnu.org, guile-devel@gnu.org User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.0.50 (gnu/linux) X-BeenThere: guile-user@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: General Guile related discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: guile-user-bounces+guile-user=m.gmane.org@gnu.org Errors-To: guile-user-bounces+guile-user=m.gmane.org@gnu.org Xref: news.gmane.org gmane.lisp.guile.user:4653 gmane.lisp.guile.devel:5171 X-Report-Spam: http://spam.gmane.org/gmane.lisp.guile.devel:5171 Hi, Guile's guardians currently make the guarantee that "it is impossible for a guardian to return a 'contained' object before its 'containing' object." I am considering removing this guarantee since it makes it impossible for guardians to deal with cycles among guarded objects, and because it is not part of the semantics of guardians as proposed in the paper by Dybvig et al[1]. So, do you rely on this ordering guarantee? If you do, you would need to take care of the ordering yourself, which is quite easy by keeping objects alive in a global data structure until they are no longer needed. [1] ftp://ftp.cs.indiana.edu/pub/scheme-repository/doc/pubs/guardians.ps.gz -- GPG: D5D4E405 - 2F9B BCCC 8527 692A 04E3 331E FAF8 226A D5D4 E405 _______________________________________________ Guile-user mailing list Guile-user@gnu.org http://lists.gnu.org/mailman/listinfo/guile-user