From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Neil Jerram Newsgroups: gmane.lisp.guile.devel Subject: Re: Backtrace and enhanced catch Date: Fri, 27 Jan 2006 19:30:07 +0000 Message-ID: <87k6cl8o5c.fsf@ossau.uklinux.net> References: <200511301616.22258.bkorb@gnu.org> <87wthpkyan.fsf@ossau.uklinux.net> <43B69F41.6030509@xs4all.nl> <87hd8pb8o7.fsf@ossau.uklinux.net> <87lkxy3abo.fsf@ossau.uklinux.net> <877j9i31gc.fsf@ossau.uklinux.net> <87acebhf1o.fsf@ossau.uklinux.net> <871wyu8t5e.fsf@zip.com.au> NNTP-Posting-Host: main.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: sea.gmane.org 1138476398 25107 80.91.229.2 (28 Jan 2006 19:26:38 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Sat, 28 Jan 2006 19:26:38 +0000 (UTC) Original-X-From: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Sat Jan 28 20:26:35 2006 Return-path: Envelope-to: guile-devel@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by ciao.gmane.org with esmtp (Exim 4.43) id 1F2viB-00046F-PP for guile-devel@m.gmane.org; Sat, 28 Jan 2006 20:26:16 +0100 Original-Received: from localhost ([127.0.0.1] helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1F2vl3-00058r-Uz for guile-devel@m.gmane.org; Sat, 28 Jan 2006 14:29:14 -0500 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1F2ZSu-0002kg-5Y for guile-devel@gnu.org; Fri, 27 Jan 2006 14:41:00 -0500 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1F2ZSp-0002jR-MU for guile-devel@gnu.org; Fri, 27 Jan 2006 14:40:58 -0500 Original-Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1F2ZNr-0001h4-I5 for guile-devel@gnu.org; Fri, 27 Jan 2006 14:35:48 -0500 Original-Received: from [80.84.72.33] (helo=mail3.uklinux.net) by monty-python.gnu.org with esmtp (Exim 4.52) id 1F2ZLe-0006xk-Hf for guile-devel@gnu.org; Fri, 27 Jan 2006 14:33:30 -0500 Original-Received: from laruns (host86-129-143-105.range86-129.btcentralplus.com [86.129.143.105]) by mail3.uklinux.net (Postfix) with ESMTP id 4896640A00A for ; Fri, 27 Jan 2006 19:32:48 +0000 (UTC) Original-Received: from laruns (laruns [127.0.0.1]) by laruns (Postfix) with ESMTP id 079256F705 for ; Fri, 27 Jan 2006 19:30:07 +0000 (GMT) Original-To: guile-devel@gnu.org In-Reply-To: <871wyu8t5e.fsf@zip.com.au> (Kevin Ryde's message of "Fri, 27 Jan 2006 10:29:49 +1100") User-Agent: Gnus/5.1007 (Gnus v5.10.7) Emacs/21.4 (gnu/linux) 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:5633 Archived-At: Kevin Ryde writes: > Neil Jerram writes: >> >> The difference is that the enclosing call approach allows >> code inbetween the lazy-catch and the error point to decide on a >> different, more local strategy for handling the error, whereas the >> hook approach doesn't. I think it's clear that the enclosing call >> approach is better, > > Yes. Making a local decision is what I always seem to use lazy-catch > for, in my case trapping selected system call errors but not > interfering with the backtrace of others. Not sure I understand. Can you point me to an example? >> the lazy-catch doc says that its handler must not return, > > It'd be nice if that could be relaxed, if it was easy to do. In a > couple of places I've wanted to return and continue past the > lazy-catch form, having taken whatever action in the handler. (An > extra wrapping full `catch' makes that possible.) Can you give an example to show what you mean? I think it's non-negotiable that if someone has coded a (throw ...) or an (error ...), execution cannot continue normally past that throw or error - but perhaps that's not what you meant? Regards, Neil _______________________________________________ Guile-devel mailing list Guile-devel@gnu.org http://lists.gnu.org/mailman/listinfo/guile-devel