From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED.blaine.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.bugs Subject: bug#37213: Execute set-window-margins. left-margin-width remains 0. Date: Thu, 29 Aug 2019 09:42:17 +0300 Message-ID: <83o908bhh2.fsf@gnu.org> References: <20190828185352.GA4530@ACM> <83r255ayq9.fsf@gnu.org> <20190828195706.GB4530@ACM> Injection-Info: blaine.gmane.org; posting-host="blaine.gmane.org:195.159.176.226"; logging-data="210289"; mail-complaints-to="usenet@blaine.gmane.org" Cc: 37213@debbugs.gnu.org To: Alan Mackenzie Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Thu Aug 29 08:43:12 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 1i3E9H-000sZp-Ej for geb-bug-gnu-emacs@m.gmane.org; Thu, 29 Aug 2019 08:43:11 +0200 Original-Received: from localhost ([::1]:45972 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i3E9F-0001uG-KP for geb-bug-gnu-emacs@m.gmane.org; Thu, 29 Aug 2019 02:43:09 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:39838) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i3E98-0001uA-VU for bug-gnu-emacs@gnu.org; Thu, 29 Aug 2019 02:43:03 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1i3E97-00083y-Us for bug-gnu-emacs@gnu.org; Thu, 29 Aug 2019 02:43:02 -0400 Original-Received: from debbugs.gnu.org ([209.51.188.43]:42697) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1i3E97-00083o-Rb for bug-gnu-emacs@gnu.org; Thu, 29 Aug 2019 02:43:01 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1i3E97-00031x-MF for bug-gnu-emacs@gnu.org; Thu, 29 Aug 2019 02:43:01 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Eli Zaretskii Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Thu, 29 Aug 2019 06:43:01 +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=B37213.156706093811594 (code B ref 37213); Thu, 29 Aug 2019 06:43:01 +0000 Original-Received: (at 37213) by debbugs.gnu.org; 29 Aug 2019 06:42:18 +0000 Original-Received: from localhost ([127.0.0.1]:51518 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1i3E8Q-00030w-Ha for submit@debbugs.gnu.org; Thu, 29 Aug 2019 02:42:18 -0400 Original-Received: from eggs.gnu.org ([209.51.188.92]:59516) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1i3E8P-00030h-IW for 37213@debbugs.gnu.org; Thu, 29 Aug 2019 02:42:18 -0400 Original-Received: from fencepost.gnu.org ([2001:470:142:3::e]:34340) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1i3E8K-0007Ru-6C; Thu, 29 Aug 2019 02:42:12 -0400 Original-Received: from [176.228.60.248] (port=2863 helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:RSA_AES_256_CBC_SHA1:256) (Exim 4.82) (envelope-from ) id 1i3E8J-00037u-DI; Thu, 29 Aug 2019 02:42:11 -0400 In-reply-to: <20190828195706.GB4530@ACM> (message from Alan Mackenzie on Wed, 28 Aug 2019 19:57:06 +0000) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] 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:166037 Archived-At: > Date: Wed, 28 Aug 2019 19:57:06 +0000 > Cc: 37213@debbugs.gnu.org > From: Alan Mackenzie > > > I don't think this is a bug. This variable is for _setting_ the > > margin width, not for _returning_ its width as set "by other means". > > See its documentation. > > 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. > > I maintain that this is either a bug in the documentation, or in the > code. I'm okay with clarifying the documentation, but let's first agree what needs clarifying there. > 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. > > 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.) Think about it: left-margin-width is a per-buffer variable. A buffer can be displayed in zero or more windows, and the margin is a window property. How can a single buffer-local variable reflect a value that can be different in different windows, and can even be meaningless if the buffer is not displayed in any window? What happens in the code is that when a buffer is displayed in a window, this variable is consulted, and the window's margin-width attribute set accordingly. The window margins can grow or shrink thereafter, and the function window-margins then returns this window attribute's value at any given moment for a specific window.