From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.bugs Subject: bug#19395: 25.0.50; Setting left fringe to 0 messes up window-width Date: Wed, 17 Dec 2014 17:29:43 +0200 Message-ID: <83d27iwazc.fsf@gnu.org> References: <87vblbnz2u.fsf@posteo.de> <83k31rwe55.fsf@gnu.org> <87lhm772o2.fsf@posteo.de> <83h9wvwbux.fsf@gnu.org> <878ui79bv7.fsf@posteo.de> Reply-To: Eli Zaretskii NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT X-Trace: ger.gmane.org 1418830229 16857 80.91.229.3 (17 Dec 2014 15:30:29 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 17 Dec 2014 15:30:29 +0000 (UTC) Cc: 19395@debbugs.gnu.org To: Titus von der Malsburg Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Wed Dec 17 16:30:22 2014 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1Y1GYP-0000KZ-0F for geb-bug-gnu-emacs@m.gmane.org; Wed, 17 Dec 2014 16:30:21 +0100 Original-Received: from localhost ([::1]:50168 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Y1GYO-0001n7-A2 for geb-bug-gnu-emacs@m.gmane.org; Wed, 17 Dec 2014 10:30:20 -0500 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:58301) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Y1GYF-0001mV-02 for bug-gnu-emacs@gnu.org; Wed, 17 Dec 2014 10:30:16 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Y1GY8-0001NO-JQ for bug-gnu-emacs@gnu.org; Wed, 17 Dec 2014 10:30:10 -0500 Original-Received: from debbugs.gnu.org ([140.186.70.43]:39625) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Y1GY8-0001N9-Fn for bug-gnu-emacs@gnu.org; Wed, 17 Dec 2014 10:30:04 -0500 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.80) (envelope-from ) id 1Y1GY7-0000Nn-Oj for bug-gnu-emacs@gnu.org; Wed, 17 Dec 2014 10:30:03 -0500 X-Loop: help-debbugs@gnu.org Resent-From: Eli Zaretskii Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Wed, 17 Dec 2014 15:30:03 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 19395 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: Original-Received: via spool by 19395-submit@debbugs.gnu.org id=B19395.14188301961432 (code B ref 19395); Wed, 17 Dec 2014 15:30:03 +0000 Original-Received: (at 19395) by debbugs.gnu.org; 17 Dec 2014 15:29:56 +0000 Original-Received: from localhost ([127.0.0.1]:48991 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1Y1GY0-0000N0-1i for submit@debbugs.gnu.org; Wed, 17 Dec 2014 10:29:56 -0500 Original-Received: from mtaout21.012.net.il ([80.179.55.169]:53286) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1Y1GXx-0000Ml-FT for 19395@debbugs.gnu.org; Wed, 17 Dec 2014 10:29:54 -0500 Original-Received: from conversion-daemon.a-mtaout21.012.net.il by a-mtaout21.012.net.il (HyperSendmail v2007.08) id <0NGQ00500G3VPA00@a-mtaout21.012.net.il> for 19395@debbugs.gnu.org; Wed, 17 Dec 2014 17:29:51 +0200 (IST) Original-Received: from HOME-C4E4A596F7 ([87.69.4.28]) by a-mtaout21.012.net.il (HyperSendmail v2007.08) with ESMTPA id <0NGQ0051XGDQOB30@a-mtaout21.012.net.il>; Wed, 17 Dec 2014 17:29:51 +0200 (IST) In-reply-to: <878ui79bv7.fsf@posteo.de> X-012-Sender: halo1@inter.net.il X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.15 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 140.186.70.43 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-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.bugs:97445 Archived-At: > From: Titus von der Malsburg > Cc: Eli Zaretskii , 19395@debbugs.gnu.org > Date: Tue, 16 Dec 2014 19:46:52 -0800 > > On 2014-12-16 Tue 15:12, Stefan Monnier wrote: > >> As long as the left fringe exists, we can display on it. But once its > >> width is zero, it no longer exists, and so we need to reserve space to > >> display the continuation glyph "by other means". > > > > That sounds wrong: if the user decides to get rid of the left-fringe, > > she just shouldn't get any continuation glyph on the left. > > Strange, setting left-fringe to 0 apparently reserves a column for the > continuation character even when the right fringe is non-zero and no > such column is needed. You are thinking only about left-to-right lines of text. But Emacs also supports right-to-left lines of text, which use the left fringe to display the continuation bitmap. Those right-to-left lines need the extra column for the continuation glyph when the left fringe is not available. And because Emacs supports mixed directions of text lines in the same buffer, and because the line geometry needs to be symmetrical in both cases, we reserve one column in left-to-right lines as well, even though the right fringe is available (and so that column will be left unused, i.e. empty, in left-to-right lines). This all is so, when neither the left nor the right fringe are available, we display mixed-direction lines like this (where "|" denotes the window edge): |left-to-right continued line\| |/RIGHT-TO-LEFT CONTINUED LINE| IOW, no matter what the direction, the text always begins at the window edge, and its last (in logical order) column is used for the continuation glyph. When the right fringe is available, but the left one isn't, you will see this instead (with "⤶" standing for the fringe bitmap: |left-to-right continued line |⤶ |/RIGHT-TO-LEFT CONTINUED LINE|