From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Matt Armstrong Newsgroups: gmane.emacs.devel Subject: Re: goto-line-history should not be buffer local. Date: Tue, 16 Feb 2021 14:52:05 -0800 Message-ID: References: <87im6ugsdq.fsf@telefonica.net> <875z2s3s9b.fsf@mail.linkov.net> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="38106"; mail-complaints-to="usenet@ciao.gmane.io" Cc: Richard Copley , martin rudalics , =?utf-8?Q?=C3=93scar?= Fuentes , Emacs Development To: Alan Mackenzie , Juri Linkov Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Tue Feb 16 23:53:04 2021 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 1lC9DK-0009l8-Ju for ged-emacs-devel@m.gmane-mx.org; Tue, 16 Feb 2021 23:53:02 +0100 Original-Received: from localhost ([::1]:43008 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lC9DJ-0000Vb-Lg for ged-emacs-devel@m.gmane-mx.org; Tue, 16 Feb 2021 17:53:01 -0500 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:41176) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lC9Cc-0008V2-HA for emacs-devel@gnu.org; Tue, 16 Feb 2021 17:52:18 -0500 Original-Received: from relay7-d.mail.gandi.net ([217.70.183.200]:59361) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lC9Ca-0005eX-7f for emacs-devel@gnu.org; Tue, 16 Feb 2021 17:52:18 -0500 X-Originating-IP: 24.113.169.116 Original-Received: from matts-mbp-2016.lan (24-113-169-116.wavecable.com [24.113.169.116]) (Authenticated sender: matt@rfc20.org) by relay7-d.mail.gandi.net (Postfix) with ESMTPSA id DAE8820002; Tue, 16 Feb 2021 22:52:09 +0000 (UTC) In-Reply-To: Received-SPF: pass client-ip=217.70.183.200; envelope-from=matt@rfc20.org; helo=relay7-d.mail.gandi.net 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, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.23 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" Xref: news.gmane.io gmane.emacs.devel:264951 Archived-At: Alan Mackenzie writes: > Hello, Juri. > > On Tue, Feb 16, 2021 at 19:13:36 +0200, Juri Linkov wrote: >> > -(defvar-local goto-line-history nil >> > +(defcustom goto-line-history-local nil >> > + "If this option is nil, `goto-line-history' is shared between all buffers. >> > +if it is non-nil, each buffer has its own value of this history list. >> > + >> > +Note that on changing from non-nil to nil, the former contents of >> > +`goto-line-history' for each buffer are discarded on use of >> > +`goto-line' in that buffer." >> > + :group 'editing >> > + :type 'boolean >> > + :safe #'booleanp >> > + :version "28.1") > >> > Anybody have any objections to this? > >> This is not an objection, just sharing a tip that to make >> Isearch history buffer-local like it's in web browsers, >> where each web page tab uses own local search history, >> is possible with a small code snippet: > >> (make-variable-buffer-local 'search-ring) >> (make-variable-buffer-local 'regexp-search-ring) > >> OTOH, with using defcustom it's easier to customize this, indeed. > > The point about the approach I've taken is that once a variable has > undergone make-variable-buffer-local, it cannot be changed back to a > non-local variable, except by restarting Emacs (I'm not sure whether or > not this is a design bug). So I've avoided the use of that primitive. Why the option at all? Why not just make the history global? I'm not strongly opposed, but I also don't think "make an option for it" is always the right thing. Who are the people who would set the option back to buffer local history? Note: the feature hasn't escaped to a stable release yet, so no strong need for an option for backward compatibility reasons. This is the strongest statement in favor of buffer locality I found: https://lists.gnu.org/r/bug-gnu-emacs/2019-11/msg01580.html: > I thought that it might be even better to have the history be > buffer-local as well; because line numbers from one buffer don't > really make sense on another. "it might be better". We've now got people who actively found it annoying. FYI we've got a similar, not yet fixed, bug about goto-char's history: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=6980. I'd say both should work a similar way, but I'm unconvinced that every such case needs an option covering a local vs. global choice.