From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED.blaine.gmane.org!not-for-mail From: Alan Mackenzie Newsgroups: gmane.emacs.bugs Subject: bug#37213: Execute set-window-margins. left-margin-width remains 0. Date: Sat, 31 Aug 2019 14:07:36 +0000 Message-ID: <20190831140736.GE4822@ACM> References: <20190828185352.GA4530@ACM> <83r255ayq9.fsf@gnu.org> <20190828195706.GB4530@ACM> <263050b1-8a57-dd39-bd49-88913935f96e@gmx.at> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Injection-Info: blaine.gmane.org; posting-host="blaine.gmane.org:195.159.176.226"; logging-data="210137"; mail-complaints-to="usenet@blaine.gmane.org" User-Agent: Mutt/1.10.1 (2018-07-13) Cc: 37213@debbugs.gnu.org To: martin rudalics Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Sat Aug 31 16:08:13 2019 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([209.51.188.17]) by blaine.gmane.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1i4433-000sae-Hm for geb-bug-gnu-emacs@m.gmane.org; Sat, 31 Aug 2019 16:08:13 +0200 Original-Received: from localhost ([::1]:44996 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i4431-0006iu-Tx for geb-bug-gnu-emacs@m.gmane.org; Sat, 31 Aug 2019 10:08:11 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:36389) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i442t-0006ic-L1 for bug-gnu-emacs@gnu.org; Sat, 31 Aug 2019 10:08:04 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1i442s-00065q-Js for bug-gnu-emacs@gnu.org; Sat, 31 Aug 2019 10:08:03 -0400 Original-Received: from debbugs.gnu.org ([209.51.188.43]:47024) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1i442s-00065f-Gf for bug-gnu-emacs@gnu.org; Sat, 31 Aug 2019 10:08:02 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1i442s-0007pE-8o for bug-gnu-emacs@gnu.org; Sat, 31 Aug 2019 10:08:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Alan Mackenzie Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Sat, 31 Aug 2019 14:08:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 37213 X-GNU-PR-Package: emacs Original-Received: via spool by 37213-submit@debbugs.gnu.org id=B37213.156726046330050 (code B ref 37213); Sat, 31 Aug 2019 14:08:02 +0000 Original-Received: (at 37213) by debbugs.gnu.org; 31 Aug 2019 14:07:43 +0000 Original-Received: from localhost ([127.0.0.1]:55845 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1i442Y-0007ob-Qb for submit@debbugs.gnu.org; Sat, 31 Aug 2019 10:07:43 -0400 Original-Received: from colin.muc.de ([193.149.48.1]:22008 helo=mail.muc.de) by debbugs.gnu.org with smtp (Exim 4.84_2) (envelope-from ) id 1i442V-0007oS-U5 for 37213@debbugs.gnu.org; Sat, 31 Aug 2019 10:07:41 -0400 Original-Received: (qmail 4509 invoked by uid 3782); 31 Aug 2019 13:14:47 -0000 Original-Received: from acm.muc.de (p2E5D5E4B.dip0.t-ipconnect.de [46.93.94.75]) by colin.muc.de (tmda-ofmipd) with ESMTP; Sat, 31 Aug 2019 15:14:45 +0200 Original-Received: (qmail 17267 invoked by uid 1000); 31 Aug 2019 14:07:36 -0000 Content-Disposition: inline In-Reply-To: <263050b1-8a57-dd39-bd49-88913935f96e@gmx.at> X-Delivery-Agent: TMDA/1.1.12 (Macallan) X-Primary-Address: acm@muc.de X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.51.188.43 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.org@gnu.org Original-Sender: "bug-gnu-emacs" Xref: news.gmane.org gmane.emacs.bugs:166116 Archived-At: Hello, Martin. On Thu, Aug 29, 2019 at 09:46:54 +0200, martin rudalics wrote: > > The documentation says "This variable specifies the width of the left > > margin". As best, this is unclear. What you're saying is that the > > variable ceases to specify that width, should the margin be altered by > > other means. > Eli didn't say that. > > I maintain that this is either a bug in the documentation, or in the > > code. > > If the former, it should explicitly state that the variable is > > write-only, and its read value is undefined. It should say that the > > function window-margins should be used instead. > The variable is not write-only and its read value is well-defined. Is the read value well-defined? Never having set it, the value it has seems always to be 0. But even if it is well-defined, is it useful for anything? > > But it might be easier just to amend the code. There appear to be just > > two ways to set the width of the left margin (or the right margin), so > > if it gets set the second way, why not just set that variable? Could > > this do any harm? (Note: I haven't looked at the code, yet.) > Please re-read the documentations of 'left-margin-width' and > 'set-window-margins' having in mind that the same buffer may appear in > different windows and the same window may show different buffers all > with differing margins. Yes, that's the thing. We don't have "window local variables" in Emacs, so anything specific to a window needs a function interface with the window being one of the parameters. > Once you've done that, please look at the respective documentations > for fringes and scroll bars which are even more complicated because > they have to obey a frame parameter as well. I've proposed a simple amendment to the "Display Margins" page of the elisp manual, saying "don't use these variables to ....!". This would solve the misunderstanding I experienced earlier. > Thanks, martin -- Alan Mackenzie (Nuremberg, Germany).