From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Stefan Monnier via "Bug reports for GNU Emacs, the Swiss army knife of text editors" Newsgroups: gmane.emacs.bugs Subject: bug#64128: regexp parser zero-width assertion bugs Date: Sat, 17 Jun 2023 14:44:30 -0400 Message-ID: References: Reply-To: Stefan Monnier Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="14572"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Cc: 64128@debbugs.gnu.org, eggert@cs.ucla.edu To: Mattias =?UTF-8?Q?Engdeg=C3=A5rd?= Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Sat Jun 17 20:45:16 2023 Return-path: Envelope-to: geb-bug-gnu-emacs@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 1qAavD-0003aP-Rt for geb-bug-gnu-emacs@m.gmane-mx.org; Sat, 17 Jun 2023 20:45:15 +0200 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qAav1-00059a-Sh; Sat, 17 Jun 2023 14:45:04 -0400 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 1qAav0-000592-2J for bug-gnu-emacs@gnu.org; Sat, 17 Jun 2023 14:45:02 -0400 Original-Received: from debbugs.gnu.org ([209.51.188.43]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1qAauz-0001Uj-Pk for bug-gnu-emacs@gnu.org; Sat, 17 Jun 2023 14:45:01 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1qAauz-00058y-Lq for bug-gnu-emacs@gnu.org; Sat, 17 Jun 2023 14:45:01 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Stefan Monnier Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Sat, 17 Jun 2023 18:45:01 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 64128 X-GNU-PR-Package: emacs X-Debbugs-Original-Cc: Emacs Bug Report , Paul Eggert Original-Received: via spool by submit@debbugs.gnu.org id=B.168702747819725 (code B ref -1); Sat, 17 Jun 2023 18:45:01 +0000 Original-Received: (at submit) by debbugs.gnu.org; 17 Jun 2023 18:44:38 +0000 Original-Received: from localhost ([127.0.0.1]:52624 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1qAauc-000585-3H for submit@debbugs.gnu.org; Sat, 17 Jun 2023 14:44:38 -0400 Original-Received: from lists.gnu.org ([209.51.188.17]:42086) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1qAauZ-00057v-Ks for submit@debbugs.gnu.org; Sat, 17 Jun 2023 14:44:36 -0400 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 1qAauZ-0004nT-Bc for bug-gnu-emacs@gnu.org; Sat, 17 Jun 2023 14:44:35 -0400 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 1qAauX-0001Rp-Uy for bug-gnu-emacs@gnu.org; Sat, 17 Jun 2023 14:44:35 -0400 Original-Received: from pmg3.iro.umontreal.ca (localhost [127.0.0.1]) by pmg3.iro.umontreal.ca (Proxmox) with ESMTP id F00F8441320; Sat, 17 Jun 2023 14:44:32 -0400 (EDT) Original-Received: from mail01.iro.umontreal.ca (unknown [172.31.2.1]) by pmg3.iro.umontreal.ca (Proxmox) with ESMTP id B83DF4412DD; Sat, 17 Jun 2023 14:44:31 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=iro.umontreal.ca; s=mail; t=1687027471; bh=Iz+hAfY16crJFWqulXlJ602BRaIsW5fS7DARLG/nT44=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=Poza0xlyMlyIn+6s5clUBKx5wjgkGDNXqr2WVB9tg2tgVisdV9cTr+Uol3/WOL7Go c94uhm366BRwMsVxt2kWwN5keUdVwLCNbTcsN4oRnKLXuFnyp5VKHUv7BEcRZm9zjs SmQ/FTh0XwzHuuCHolW7DluykrHpP3rE5UIAr9DNSlKH0JN+JkWElWbKvU0wBba+ot I73zmE/BVz+51/A7rXCBRt83Vl0db+CYvZwqTmqvut9shsOskTiJJZJBgUCukYG8rS zoILmp4DWkC8fXLgOsQXh4qzAdc7iOMu0SZ3Gyhm1DaOjZ2ACgMFvQ/bqJfVucOgGy vBSZ0JI3gzVxw== Original-Received: from pastel (unknown [45.72.207.87]) by mail01.iro.umontreal.ca (Postfix) with ESMTPSA id 8E7AC12013F; Sat, 17 Jun 2023 14:44:31 -0400 (EDT) In-Reply-To: ("Mattias =?UTF-8?Q?Engdeg=C3=A5rd?="'s message of "Sat, 17 Jun 2023 14:20:27 +0200") 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: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-BeenThere: bug-gnu-emacs@gnu.org List-Id: "Bug reports for GNU Emacs, the Swiss army knife of text editors" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Original-Sender: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.bugs:263569 Archived-At: > (and (string-match "quack,\\b*" "quack,quack,quack,quaaaack!") > (match-data)) > => (0 18) That's so bizarre that it feels like we really should try and preserve it for posterity. Not. > These regexp patterns should be very rare in practice: they should > always be a mistake, but it would be nice if they behaved in a way > that makes some kind of sense. > > A modest improvement would be to make operators become literal after > any zero-width assertion, so that I think the behavior that makes most sense is to signal an error when compiling the regexp. Stefan