From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Stefan Monnier Newsgroups: gmane.emacs.devel Subject: Re: Attaching context info to an error Date: Tue, 26 Dec 2023 15:47:23 -0500 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="35503"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Cc: emacs-devel@gnu.org To: =?windows-1252?B?Sm/jbyBU4XZvcmE=?= Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Tue Dec 26 21:48:19 2023 Return-path: Envelope-to: ged-emacs-devel@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1rIELb-00090l-EO for ged-emacs-devel@m.gmane-mx.org; Tue, 26 Dec 2023 21:48:19 +0100 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rIEKt-0002R2-Gy; Tue, 26 Dec 2023 15:47:35 -0500 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rIEKs-0002Qu-Ko for emacs-devel@gnu.org; Tue, 26 Dec 2023 15:47:34 -0500 Original-Received: from mailscanner.iro.umontreal.ca ([132.204.25.50]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rIEKq-0005A1-Uf for emacs-devel@gnu.org; Tue, 26 Dec 2023 15:47:34 -0500 Original-Received: from pmg3.iro.umontreal.ca (localhost [127.0.0.1]) by pmg3.iro.umontreal.ca (Proxmox) with ESMTP id 12A70442216; Tue, 26 Dec 2023 15:47:31 -0500 (EST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=iro.umontreal.ca; s=mail; t=1703623645; bh=YbzGqhU/ps5LM98TQvLMxpVQqXCUQ/0duY5uEANnErs=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=g/fPq6TnEImu9Uf0Uz0ucJekJsCk0jdIWOUy8paemLXNt8G4IE9k99Z8l7dIq655X ohtLKhBO4pDTpDmgtw9+4bnCIyx0OI7VYVCSmXzoUh/PnlIpwTQ8k5XS26qEpEP3MU wS9q61INFyxjiTaMVh82teBwCYi/85T5i5w82rR9VbZfk16Wk99sGdGYROS2Mal6WH ltxjmJJq+ZOh4UoQhS1xiOzi6UxHo+dSxSxhph75Os1rrEs9+9BXIZ3neEbDXdBGWc 8jLgxaVPhETSCAjShStXB6lCsesMoajJ0UmDevHdWThhiaeN+HdMIraEV64JuoLGv5 9m4+boCBeQZhQ== Original-Received: from mail01.iro.umontreal.ca (unknown [172.31.2.1]) by pmg3.iro.umontreal.ca (Proxmox) with ESMTP id 7D180442214; Tue, 26 Dec 2023 15:47:25 -0500 (EST) Original-Received: from pastel (65-110-221-238.cpe.pppoe.ca [65.110.221.238]) by mail01.iro.umontreal.ca (Postfix) with ESMTPSA id 57C34121071; Tue, 26 Dec 2023 15:47:25 -0500 (EST) In-Reply-To: (=?windows-1252?Q?=22Jo=E3o_T=E1vora=22's?= message of "Sat, 23 Dec 2023 03:02:04 +0000") Received-SPF: pass client-ip=132.204.25.50; envelope-from=monnier@iro.umontreal.ca; helo=mailscanner.iro.umontreal.ca X-Spam_score_int: -42 X-Spam_score: -4.3 X-Spam_bar: ---- X-Spam_report: (-4.3 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.devel:314230 Archived-At: >> I'm playing with `handler-bind` and trying to see how we could make use >> of such a functionality in Emacs. > *loud cheers* [...] > Amongst the killer weaponry this gives us is a restart system, > finally. I fail to see the connection, to be honest. > (defun pm/call-with-retry-restart (outer inner msg fn) > (catch outer > (let ((saved-restarts pm/restarts)) > (unwind-protect > (while t > (catch inner > (handler-bind ((error (lambda (_e) > (push > (list 'retry msg > (lambda () > (throw inner nil))) > pm/restarts)))) > (throw outer (funcall fn))))) > (setq pm/restarts saved-restarts))))) Rather than `(let ((saved-restarts pm/restarts))` why not `(let ((pm/restarts pm/restarts))` so you don't need the `setq` in the `unwind-protect`? And why `handler-bind`. IOW, why wait until the error happens before pushing the retry onto the list? Why not just: (defun pm/call-with-retry-restart (outer inner msg fn) (catch outer (let ((pm/restarts (cons (list 'retry msg (lambda () (throw inner nil)))))) (while t (catch inner (throw outer (funcall fn))))))) -- Stefan