From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Gregory Heytings Newsgroups: gmane.emacs.bugs Subject: bug#56682: locked narrowing Date: Fri, 02 Dec 2022 08:04:06 +0000 Message-ID: <20f32a53dc3b247b0b00@heytings.org> References: <97049541-f5b4-ed3b-b8de-7c0bdc86f0f5@yandex.ru> <6e305c9b-7702-133a-3347-f64db05ade3f@yandex.ru> <83mt89kt10.fsf@gnu.org> <834juglesn.fsf@gnu.org> <83r0xkjw5s.fsf@gnu.org> <83pmd3ioxx.fsf@gnu.org> <47153506021498df087c@heytings.org> <83bkomhlmn.fsf@gnu.org> <4715350602cf2ec6860b@heytings.org> <83a646hkat.fsf@gnu.org> <47153506028bbb3bc8b3@heytings.org> <47153506021115866615@heytings.org> <834juegs87.fsf@gnu.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="5631"; mail-complaints-to="usenet@ciao.gmane.io" Cc: 56682@debbugs.gnu.org, Stefan Monnier , dgutov@yandex.ru To: Eli Zaretskii Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Fri Dec 02 09:05:27 2022 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 1p1131-0001HP-48 for geb-bug-gnu-emacs@m.gmane-mx.org; Fri, 02 Dec 2022 09:05:27 +0100 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1p112q-0006kb-8Z; Fri, 02 Dec 2022 03:05:19 -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 1p112c-0006jh-CB for bug-gnu-emacs@gnu.org; Fri, 02 Dec 2022 03:05:03 -0500 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 1p112b-0000V5-SI for bug-gnu-emacs@gnu.org; Fri, 02 Dec 2022 03:05:02 -0500 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1p112b-0003RT-OL for bug-gnu-emacs@gnu.org; Fri, 02 Dec 2022 03:05:01 -0500 X-Loop: help-debbugs@gnu.org Resent-From: Gregory Heytings Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Fri, 02 Dec 2022 08:05:01 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 56682 X-GNU-PR-Package: emacs Original-Received: via spool by 56682-submit@debbugs.gnu.org id=B56682.166996824913217 (code B ref 56682); Fri, 02 Dec 2022 08:05:01 +0000 Original-Received: (at 56682) by debbugs.gnu.org; 2 Dec 2022 08:04:09 +0000 Original-Received: from localhost ([127.0.0.1]:45167 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1p111l-0003R7-JA for submit@debbugs.gnu.org; Fri, 02 Dec 2022 03:04:09 -0500 Original-Received: from heytings.org ([95.142.160.155]:40432) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1p111j-0003R0-KO for 56682@debbugs.gnu.org; Fri, 02 Dec 2022 03:04:07 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=heytings.org; s=20220101; t=1669968247; bh=kv2xQqUYsHRFSQf8k5kby1vBNl4enpJh3NXX8jg4vYU=; h=Date:From:To:cc:Subject:In-Reply-To:Message-ID:References:From; b=y3At9nuhCsnHmy1gWYEYNNdu/dXCCfp/h9JWAwhqbtCpu4WSbC88bzzsdjjSLRQ63 QJkjtM175bOxWI4CkKjZNh2x4wwfRJHDSEhdYGtHBqLK3tiqlBKu6LNF7ZAvV7+QGq SZ/Uanko2txjYCbEg7fvQ+XjB9nfedEOOPI1dgqMEc/MrvBrsyFq85le0YvhnXlj/8 KXnjR1BaXwoDqLqaK+xpkYWOSZvS7QSDkzopulM/kkRvNQ5n2dVFyu/u6iCQ53Ltn/ OEIperahCDAjIuVp+BoOu8C1Wyr72TKy1f5qOTpiFD5aG4PEYNbpwcR+fVoJJox9n9 ppBogsA46gffg== In-Reply-To: <834juegs87.fsf@gnu.org> 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:249714 Archived-At: > > We only need to know whether there are long lines in a region around > point that is large enough to make sure redisplay won't look beyond > that. > Sorry, but no, we don't. > > (Gregory disagrees, but I have yet to see a reason why he would be right > and I would be wrong in this matter.) > Consider this other scenario. A buffer is buried, and modified in the background by some process. That process adds a long line in that buffer, followed by enough non-long lines, with point after these non-long lines. Now the user asks for that buffer to be displayed again. With your proposed approach, we would search around point if there are long lines. There aren't, so we do not activate long line optimizations. Now the user scrolls the buffer. The buffer has not changed in any way, so the detection is not triggered, and we reach the long line. Kaboom!