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: array handles and non-local exits Date: Thu, 18 Sep 2008 10:15:59 +0200 Message-ID: <87myi5g98g.fsf@gnu.org> References: <49dd78620809151317i3421081ey3337d678477046ab@mail.gmail.com> <87ljxsv80p.fsf@gnu.org> <49dd78620809171232n745ac8ecgd2c3936989ce723b@mail.gmail.com> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: ger.gmane.org 1221725842 818 80.91.229.12 (18 Sep 2008 08:17:22 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Thu, 18 Sep 2008 08:17:22 +0000 (UTC) To: guile-devel@gnu.org Original-X-From: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Thu Sep 18 10:18:19 2008 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 4.50) id 1KgEiQ-00072t-EL for guile-devel@m.gmane.org; Thu, 18 Sep 2008 10:18:18 +0200 Original-Received: from localhost ([127.0.0.1]:37910 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1KgEhO-00013B-Tr for guile-devel@m.gmane.org; Thu, 18 Sep 2008 04:17:14 -0400 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1KgEgT-0000oc-KR for guile-devel@gnu.org; Thu, 18 Sep 2008 04:16:17 -0400 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1KgEgR-0000ni-CQ for guile-devel@gnu.org; Thu, 18 Sep 2008 04:16:17 -0400 Original-Received: from [199.232.76.173] (port=41262 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1KgEgR-0000nZ-7Q for guile-devel@gnu.org; Thu, 18 Sep 2008 04:16:15 -0400 Original-Received: from main.gmane.org ([80.91.229.2]:49984 helo=ciao.gmane.org) by monty-python.gnu.org with esmtps (TLS-1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1KgEgR-00034v-Fu for guile-devel@gnu.org; Thu, 18 Sep 2008 04:16:15 -0400 Original-Received: from list by ciao.gmane.org with local (Exim 4.43) id 1KgEgJ-0000YC-Et for guile-devel@gnu.org; Thu, 18 Sep 2008 08:16:07 +0000 Original-Received: from 193.50.110.60 ([193.50.110.60]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 18 Sep 2008 08:16:07 +0000 Original-Received: from ludo by 193.50.110.60 with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 18 Sep 2008 08:16:07 +0000 X-Injected-Via-Gmane: http://gmane.org/ Original-Lines: 51 Original-X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: 193.50.110.60 X-URL: http://www.fdn.fr/~lcourtes/ X-Revolutionary-Date: Jour du Travail de =?iso-8859-1?Q?l'Ann=E9e?= 216 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: 821D 815D 902A 7EAB 5CEE D120 7FBA 3D4F EB1F 5364 X-OS: i686-pc-linux-gnu User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.3 (gnu/linux) Cancel-Lock: sha1:D9iTQNNXLG/HQ8+lUh044s2WLds= X-detected-operating-system: by monty-python.gnu.org: GNU/Linux 2.6, seldom 2.4 (older, 4) 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:7717 Archived-At: Hi, "Neil Jerram" writes: >>>> and (2) I don't know of any other function that does a dynwind behind >>>> the scenes (IOW, let's not break the "rule of least surprise"). >> >> I meant "I don't know of a function that does a `dynwind_begin' >> *alone*" (of course there are plenty of functions that do >> `dynwind_begin' + `dynwind_end'). > > Yes, I see what you mean now. (The scm_dynwind_begin() being in > scm_array_get_handle(), and the scm_dynwind_end() being in > scm_array_release_handle().) Yes. >>> I think you're imagining a clear boundary here where there isn't one. >>> If needed, either the scm_dynwind would be inside >>> scm_array_get_handle, or it would be inside scm_uniform_vector_read. >>> Both of those are public libguile functions, so where's the >>> difference? >> >> The difference is that `scm_array_get_handle ()' is a low-level >> function. It may be used, say, in code that passes SRFI-4 vectors to C >> that implements "performance-critical" code. Adding consing in there >> wouldn't feel right. > > If you add in " and which can't possibly do a non-local exit " there, > I see your point. Exactly. >> Right, I hadn't thought about it, but as you mention, a dynwind in >> `uniform-vector-read!' will only affect soft port implementations. > > With that in mind, do you think we need to solve this now? I think > this is low impact, so for now I'm inclined just to raise a bug in > Savannah, containing our discussion so far, so that we don't forget > it. I submitted this bug: https://savannah.gnu.org/bugs/index.php?24292 (Oops I forgot "and dynwinds" in the bug title...) I would suggest that we drop that mention of dynwinds from the manual. Thanks, Ludo'.