From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: Bidirectional text and URLs Date: Thu, 04 Dec 2014 19:30:58 +0200 Message-ID: <83lhmn490t.fsf@gnu.org> References: <87a93cngwv.fsf@uwakimon.sk.tsukuba.ac.jp> <837fyfml31.fsf@gnu.org> <874mtio7wh.fsf@uwakimon.sk.tsukuba.ac.jp> <83r3wml8kq.fsf@gnu.org> <83a938aeuc.fsf@gnu.org> <838uir8huv.fsf@gnu.org> <83388y6rb3.fsf@gnu.org> <83mw7463cz.fsf@gnu.org> Reply-To: Eli Zaretskii NNTP-Posting-Host: plane.gmane.org X-Trace: ger.gmane.org 1417714269 29795 80.91.229.3 (4 Dec 2014 17:31:09 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Thu, 4 Dec 2014 17:31:09 +0000 (UTC) Cc: larsi@gnus.org, rms@gnu.org, emacs-devel@gnu.org To: Stefan Monnier Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Thu Dec 04 18:31:00 2014 Return-path: Envelope-to: ged-emacs-devel@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 1XwaF1-0005yO-OJ for ged-emacs-devel@m.gmane.org; Thu, 04 Dec 2014 18:30:59 +0100 Original-Received: from localhost ([::1]:46907 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XwaF1-0000Y0-D6 for ged-emacs-devel@m.gmane.org; Thu, 04 Dec 2014 12:30:59 -0500 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:49535) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XwaEt-0000Xs-Ni for emacs-devel@gnu.org; Thu, 04 Dec 2014 12:30:57 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XwaEo-0006AG-Ee for emacs-devel@gnu.org; Thu, 04 Dec 2014 12:30:51 -0500 Original-Received: from mtaout22.012.net.il ([80.179.55.172]:53212) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XwaEo-00069w-6G; Thu, 04 Dec 2014 12:30:46 -0500 Original-Received: from conversion-daemon.a-mtaout22.012.net.il by a-mtaout22.012.net.il (HyperSendmail v2007.08) id <0NG200K00J8T9G00@a-mtaout22.012.net.il>; Thu, 04 Dec 2014 19:30:44 +0200 (IST) Original-Received: from HOME-C4E4A596F7 ([87.69.4.28]) by a-mtaout22.012.net.il (HyperSendmail v2007.08) with ESMTPA id <0NG200J20JB8ZZ50@a-mtaout22.012.net.il>; Thu, 04 Dec 2014 19:30:44 +0200 (IST) In-reply-to: X-012-Sender: halo1@inter.net.il X-detected-operating-system: by eggs.gnu.org: Solaris 10 X-Received-From: 80.179.55.172 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.14 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.org@gnu.org Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:178840 Archived-At: > From: Stefan Monnier > Cc: Eli Zaretskii , larsi@gnus.org, emacs-devel@gnu.org > Date: Thu, 04 Dec 2014 10:53:29 -0500 > > The problematic case that started this thread was because strongly L2R > characters were displayed in R2L fashion because of their context. > And *that* is indeed a problem, because there was no obvious visual > clue: the reversed chars were all latin chars. We now have a primitive that can be used to detect such regions in a buffer. So we can implement a warning in those cases. > So, if we want to emit a warning, it should not be when "there's some > R2L text in an L2R context" but only when L2R characters end up layed out in > R2L because of the context. And likewise with R2L characters that end up displayed left to right (although the target audience for this would be much smaller). > I'm not familiar enough with bidi uses to know for sure whether such > "forced wrong-way layout" is something that can occur regularly in > normal/legitimate situations There's no reason for it to occur regularly. Its main purpose is to satisfy very specific and rare circumstances, like when you need to show R2L text in logical order (e.g., for didactic reasons), or force punctuation characters to display in a particular visual order.