From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Marcin Borkowski Newsgroups: gmane.emacs.help Subject: Is there a way to know if this-command altered the buffer? Date: Wed, 12 May 2021 05:33:30 +0200 Message-ID: <87tun8wrqt.fsf@mbork.pl> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="727"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: mu4e 1.1.0; emacs 28.0.50 To: Help Gnu Emacs mailing list Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Wed May 12 05:34:48 2021 Return-path: Envelope-to: geh-help-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 1lgfe3-000AYv-LD for geh-help-gnu-emacs@m.gmane-mx.org; Wed, 12 May 2021 05:34:47 +0200 Original-Received: from localhost ([::1]:59126 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lgfe2-0003lA-Jz for geh-help-gnu-emacs@m.gmane-mx.org; Tue, 11 May 2021 23:34:46 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:43510) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lgfdR-0003km-5x for help-gnu-emacs@gnu.org; Tue, 11 May 2021 23:34:09 -0400 Original-Received: from mail.mojserwer.eu ([195.110.48.8]:53842) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lgfdL-0000VG-BN for help-gnu-emacs@gnu.org; Tue, 11 May 2021 23:34:08 -0400 Original-Received: from localhost (localhost [127.0.0.1]) by mail.mojserwer.eu (Postfix) with ESMTP id 1CF2DE6590 for ; Wed, 12 May 2021 05:33:48 +0200 (CEST) X-Virus-Scanned: Debian amavisd-new at mail.mojserwer.eu Original-Received: from mail.mojserwer.eu ([127.0.0.1]) by localhost (mail.mojserwer.eu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 3kxIjcEHiwGA for ; Wed, 12 May 2021 05:33:42 +0200 (CEST) Original-Received: from localhost (178235147191.dynamic-3-poz-k-0-1-0.vectranet.pl [178.235.147.191]) by mail.mojserwer.eu (Postfix) with ESMTPSA id 5A503E6209 for ; Wed, 12 May 2021 05:33:41 +0200 (CEST) Received-SPF: pass client-ip=195.110.48.8; envelope-from=mbork@mbork.pl; helo=mail.mojserwer.eu X-Spam_score_int: -25 X-Spam_score: -2.6 X-Spam_bar: -- X-Spam_report: (-2.6 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_PASS=-0.001, T_SPF_HELO_TEMPERROR=0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Users list for the GNU Emacs text editor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Original-Sender: "help-gnu-emacs" Xref: news.gmane.io gmane.emacs.help:129711 Archived-At: Hi all, I want to run some function in a certain hook. This function will update some info displayed using an overlay. The info depends on the buffer contents and is pretty expensive to compute, so I'd like to only display it if the buffer really changed. Is there a way to know if `this-command' actually changed the buffer (as opposed to e.g. point motion)? TIA, -- Marcin Borkowski http://mbork.pl