From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: =?UTF-8?B?Sm/Do28gVMOhdm9yYQ==?= Newsgroups: gmane.emacs.devel Subject: Re: Attaching context info to an error Date: Sat, 23 Dec 2023 03:02:04 +0000 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="39223"; mail-complaints-to="usenet@ciao.gmane.io" Cc: emacs-devel@gnu.org To: Stefan Monnier Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Sat Dec 23 04:03:06 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 1rGsI6-0009xd-6X for ged-emacs-devel@m.gmane-mx.org; Sat, 23 Dec 2023 04:03:06 +0100 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rGsHO-00032o-4g; Fri, 22 Dec 2023 22:02:22 -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 1rGsHM-00032b-CN for emacs-devel@gnu.org; Fri, 22 Dec 2023 22:02:20 -0500 Original-Received: from mail-lj1-x232.google.com ([2a00:1450:4864:20::232]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1rGsHK-0005SQ-Ni for emacs-devel@gnu.org; Fri, 22 Dec 2023 22:02:20 -0500 Original-Received: by mail-lj1-x232.google.com with SMTP id 38308e7fff4ca-2cc5ee69960so25984811fa.0 for ; Fri, 22 Dec 2023 19:02:18 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1703300537; x=1703905337; darn=gnu.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=AffoXkDMDNbpetoC0I1w1c8Yf7jEvLr6HL7a/LlSl8g=; b=D6T+UTSifsS4+a4ecP/Zam6taimjHOfI3jajxvkwG0EufzvV8XtTHfUz7+i6Dbnwhu yiOEPj6HBhBq1bw59OzRWhCZA1Kd+VtIjJNabBhl55TV8yEGd/Zc78Il7+IlNCF0Yo6Z ip9F30lhB4s+Qigb/AgmdGMma6natElykSoxceOVtYFk21R8NMfYIkFNog1XS9y8yeK3 d4ZlqKI/yJOZr08Qib8F/CZiLoxZKrGgnv+KW6B/N2BKMqp9JtA1Ztnv/cuMgCBd6URO QCnzYyTWS1Dn6oNwV6EVqvkvsembohuuCFxpksl0r5SOJudV7h6lKBgaeJz7yhcVaYb1 O96Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1703300537; x=1703905337; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=AffoXkDMDNbpetoC0I1w1c8Yf7jEvLr6HL7a/LlSl8g=; b=BdiZFGVnj2+IXl31HG3SWmgAgyQftoeo0DP6wH2YliU/P9aaXmdK8zTZfm7MX1cXHV bBPjbQMMdmbtrgWeo/R+//z5pgpWljfqUKx7qvTHnP+hAU9726CIkjYGHpvgPeWsMyfq Fbot0dG6aGqCQsWQ8a7re96oB6cDvBVylcRJbd3h3asZbXVTmsGxrEk6FKtDYrvIV2V3 ycedA9Pgrk4FPvlqr/qmorFkMtZFlp2va1UDpzJ4K405IosDVJDgjgTuNnZod9gxqH9n I13AHGnOgjjySMlL6PBdqSKKB8YuExYshrCOYDFSL1Ksdc8xDRJ+CUeJB3kBWxdN/XQJ h1OQ== X-Gm-Message-State: AOJu0Ywt4ODS9KIPycWU5OYxm6YBAHNvTXlPeVpTgqb8ivpGACt8vYBS lUPQ3ylv5gW8XrzShhB3Uyv1/256P3oqQqsyOLk= X-Google-Smtp-Source: AGHT+IFPTWRheaIWEZJFZAK0pTpjmqEVGHsN+kFBeGx/ZzZAXU6J04+jUeoeL/aeCJAoygAjRse5txx7/SDseG43Y5w= X-Received: by 2002:a05:651c:2044:b0:2cc:7868:c200 with SMTP id t4-20020a05651c204400b002cc7868c200mr622260ljo.90.1703300536518; Fri, 22 Dec 2023 19:02:16 -0800 (PST) In-Reply-To: Received-SPF: pass client-ip=2a00:1450:4864:20::232; envelope-from=joaotavora@gmail.com; helo=mail-lj1-x232.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_NONE=-0.0001, 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:314092 Archived-At: On Thu, Dec 21, 2023 at 10:31=E2=80=AFPM Stefan Monnier wrote: > I'm playing with `handler-bind` and trying to see how we could make use > of such a functionality in Emacs. *loud cheers* > So far I have encountered basically two use case: (...proceeds to list three use cases...) Amongst the killer weaponry this gives us is a restart system, finally. This completely changes interactive development. Whereas before you couldn't restart from an nearby stack frame after doing some changes to the state (say recompiling a buggy function, or setting a global variable), with a handler-bind-powered restart system you finally can. So I had to try your branch... ;; -*- lexical-binding: t -*- (require 'cl-lib) (defvar pm/restarts nil) (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))))) (cl-defmacro pm/with-retry-restart ((&key (msg "Retry.")) &body body) `(pm/call-with-retry-restart (gensym) (gensym) ,msg (lambda () ,@body))) (defun pm/invoke-restart (restart) (interactive (some-read-from-minibuffer-or-somesuch)) (funcall (caadr restart))) (defun baz (sym) (error "whoops, it happened again for %s" sym)) (defun bar () (pm/with-retry-restart (:msg "Retry") (baz (gensym)))) (defun foo () (bar)) (foo) ;; Local Variables: ;; read-symbol-shorthands: (("pm/" . "poor-mans-restarts-")) ;; End: This very code works fine in Common Lisp (just add a WHILE macro to it) however when I try this in your Emacs branch and evaluate (foo) I get: Re-entering top level after C stack overflow and Emacs dies immediately. Jo=C3=A3o PS: Of course Common Lisp has all of this built-in and with much, much better primitives that cover a wealth of use cases. So this was just a quick-n-dirty proof of concept.