From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.bidi,gmane.emacs.devel Subject: Re: Re: Column numbering in bidirectional display Date: Fri, 21 May 2010 14:17:54 +0300 Message-ID: <83zkztzeot.fsf@gnu.org> References: <83tyq1pqov.fsf@gnu.org> <87y6fdppp7.fsf@lola.goethe.zz> Reply-To: Eli Zaretskii NNTP-Posting-Host: lo.gmane.org X-Trace: dough.gmane.org 1274440724 23015 80.91.229.12 (21 May 2010 11:18:44 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Fri, 21 May 2010 11:18:44 +0000 (UTC) Cc: emacs-bidi@gnu.org, emacs-devel@gnu.org To: David Kastrup Original-X-From: emacs-bidi-bounces+gnu-emacs-bidi=m.gmane.org@gnu.org Fri May 21 13:18:43 2010 connect(): No such file or directory Return-path: Envelope-to: gnu-emacs-bidi@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1OFQFU-0005WU-Iz for gnu-emacs-bidi@m.gmane.org; Fri, 21 May 2010 13:18:40 +0200 Original-Received: from localhost ([127.0.0.1]:54502 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1OFQFT-0006SG-ME for gnu-emacs-bidi@m.gmane.org; Fri, 21 May 2010 07:18:39 -0400 Original-Received: from [140.186.70.92] (port=47081 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1OFQFO-0006QY-7Y for emacs-bidi@gnu.org; Fri, 21 May 2010 07:18:35 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69) (envelope-from ) id 1OFQFM-0006iq-7b for emacs-bidi@gnu.org; Fri, 21 May 2010 07:18:34 -0400 Original-Received: from mtaout22.012.net.il ([80.179.55.172]:36569) by eggs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1OFQFI-0006hn-Rw; Fri, 21 May 2010 07:18:29 -0400 Original-Received: from conversion-daemon.a-mtaout22.012.net.il by a-mtaout22.012.net.il (HyperSendmail v2007.08) id <0L2R00700NW3I200@a-mtaout22.012.net.il>; Fri, 21 May 2010 14:17:56 +0300 (IDT) Original-Received: from HOME-C4E4A596F7 ([77.127.33.125]) by a-mtaout22.012.net.il (HyperSendmail v2007.08) with ESMTPA id <0L2R0066OOPUAY50@a-mtaout22.012.net.il>; Fri, 21 May 2010 14:17:55 +0300 (IDT) In-reply-to: <87y6fdppp7.fsf@lola.goethe.zz> X-012-Sender: halo1@inter.net.il X-detected-operating-system: by eggs.gnu.org: Solaris 10 (beta) X-BeenThere: emacs-bidi@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Discussion of Emacs support for multi-directional text." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: emacs-bidi-bounces+gnu-emacs-bidi=m.gmane.org@gnu.org Errors-To: emacs-bidi-bounces+gnu-emacs-bidi=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.bidi:615 gmane.emacs.devel:124986 Archived-At: > From: David Kastrup > Date: Fri, 21 May 2010 11:30:12 +0200 > Cc: emacs-devel@gnu.org > > It is my opinion that bidi reordering should be kept strictly a display > feature. Just so I'm sure I understand what you are saying: do you agree that current-column should return a logical-order column number it does today? > A command like vertical-motion acts on a display text presentation > rather than a logical representation: it would heed bidi (where > applicable). This already works, as long as all paragraphs have the same direction, either L2R or R2L. The cursor is placed on characters whose visual distance from the window margin is the same (as far as the line's length allows that). That's because the display engine internally keeps the correct horizontal position of each glyph, after reordering, and the various routines that move in ``display line'' use bidi iteration. I will probably need to fix this for when paragraph direction changes; currently, Emacs puts the cursor at the same distance from the other edge of the window, which is not terribly wrong, but I think users will not expect that. However, note that if this is fixed, the value of current-column will change when point moves from a L2R paragraph to a R2L one or vice versa. > Programmatically, text manipulation should keep as far away from those > display-oriented functions as possible (except where indeed the display > representation should be manipulated). And all basic text manipulation > should stay Hmm, looks unfinished. Anyway, thanks for the feedback.