From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: ludo@gnu.org (Ludovic =?iso-8859-1?Q?Court=E8s?=) Newsgroups: gmane.lisp.guile.devel Subject: Re: [PATCH 3/4] Work towards a more complete implementation of `(rnrs io ports)' Date: Wed, 24 Nov 2010 21:24:28 +0100 Message-ID: <878w0i79mr.fsf@gnu.org> References: <87d3pyz5yo.fsf@delenn.lan> <1290377874-13808-3-git-send-email-a.rottmann@gmx.at> <8762vn3fro.fsf@gnu.org> <87d3pvli4p.fsf@delenn.lan> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Trace: dough.gmane.org 1290630326 15372 80.91.229.12 (24 Nov 2010 20:25:26 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Wed, 24 Nov 2010 20:25:26 +0000 (UTC) To: guile-devel@gnu.org Original-X-From: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Wed Nov 24 21:25:22 2010 Return-path: Envelope-to: guile-devel@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1PLLu3-0000MA-LZ for guile-devel@m.gmane.org; Wed, 24 Nov 2010 21:25:19 +0100 Original-Received: from localhost ([127.0.0.1]:58719 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PLLu3-0005qn-0C for guile-devel@m.gmane.org; Wed, 24 Nov 2010 15:25:19 -0500 Original-Received: from [140.186.70.92] (port=33529 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PLLtw-0005qC-MK for guile-devel@gnu.org; Wed, 24 Nov 2010 15:25:13 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1PLLtv-0002QF-8w for guile-devel@gnu.org; Wed, 24 Nov 2010 15:25:12 -0500 Original-Received: from lo.gmane.org ([80.91.229.12]:41920) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1PLLtu-0002QB-Uy for guile-devel@gnu.org; Wed, 24 Nov 2010 15:25:11 -0500 Original-Received: from list by lo.gmane.org with local (Exim 4.69) (envelope-from ) id 1PLLto-0000Co-M9 for guile-devel@gnu.org; Wed, 24 Nov 2010 21:25:04 +0100 Original-Received: from yoda.fdn.fr ([80.67.169.18]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 24 Nov 2010 21:25:04 +0100 Original-Received: from ludo by yoda.fdn.fr with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 24 Nov 2010 21:25:04 +0100 X-Injected-Via-Gmane: http://gmane.org/ Original-Lines: 28 Original-X-Complaints-To: usenet@dough.gmane.org X-Gmane-NNTP-Posting-Host: yoda.fdn.fr X-URL: http://www.fdn.fr/~lcourtes/ X-Revolutionary-Date: 4 Frimaire an 219 de la =?iso-8859-1?Q?R=E9volution?= X-PGP-Key-ID: 0xEA52ECF4 X-PGP-Key: http://www.fdn.fr/~lcourtes/ludovic.asc X-PGP-Fingerprint: 83C4 F8E5 10A3 3B4C 5BEA D15D 77DD 95E2 EA52 ECF4 X-OS: x86_64-unknown-linux-gnu User-Agent: Gnus/5.110011 (No Gnus v0.11) Emacs/23.2 (gnu/linux) Cancel-Lock: sha1:yA/SsO4umajdnGUKcq4cLZDZ6J0= X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6 (newer, 3) X-BeenThere: guile-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Developers list for Guile, the GNU extensibility library" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Errors-To: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.lisp.guile.devel:11197 Archived-At: Hi, Andreas Rottmann writes: > To quote that paragraph about `call-with-port': > > ,---- > | Proc must accept one argument. The call-with-port procedure calls proc > | with port as an argument. If proc returns, port is closed automatically > | and the values returned by proc are returned. If proc does not return, > | port is not closed automatically, except perhaps when it is possible to > | prove that port will never again be used for an input or output > | operation. > `---- > > I interpreted that the way I did based on the question of what should > happen when `proc' throws an exception (or otherwise invokes a > continuation that makes it leave its current dynamic extent). To me, it > seems that in this case, `proc' does not _return_, and hence the port > should not be closed. Just to clarify, by a procedure "returning", I > understand delivering a value (or values) to its continuation, which > does not happen if the procedure invokes some arbitrary (other) > continuation. Oh, yes, makes sense to me now. Thanks, Ludo’.