From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Richard Stallman Newsgroups: gmane.emacs.devel,gmane.emacs.bidi Subject: Re: Mixed L2R and R2L paragraphs and horizontal scroll Date: Mon, 01 Feb 2010 16:05:19 -0500 Message-ID: References: <83tyu3iu6b.fsf@gnu.org> <837hqyi1h7.fsf@gnu.org> Reply-To: rms@gnu.org NNTP-Posting-Host: lo.gmane.org Content-Type: text/plain; charset=ISO-8859-15 X-Trace: ger.gmane.org 1265058398 28846 80.91.229.12 (1 Feb 2010 21:06:38 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Mon, 1 Feb 2010 21:06:38 +0000 (UTC) Cc: emacs-bidi@gnu.org, emacs-devel@gnu.org To: Eli Zaretskii Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Mon Feb 01 22:06:34 2010 Return-path: Envelope-to: ged-emacs-devel@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 1Nc3TQ-0000FT-BY for ged-emacs-devel@m.gmane.org; Mon, 01 Feb 2010 22:06:20 +0100 Original-Received: from localhost ([127.0.0.1]:34442 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Nc3TP-0000Uk-T1 for ged-emacs-devel@m.gmane.org; Mon, 01 Feb 2010 16:06:19 -0500 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1Nc3SV-0008Qu-3j for emacs-devel@gnu.org; Mon, 01 Feb 2010 16:05:23 -0500 Original-Received: from [199.232.76.173] (port=50948 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Nc3ST-0008Q8-NB for emacs-devel@gnu.org; Mon, 01 Feb 2010 16:05:21 -0500 Original-Received: from Debian-exim by monty-python.gnu.org with spam-scanned (Exim 4.60) (envelope-from ) id 1Nc3SS-0002RQ-81 for emacs-devel@gnu.org; Mon, 01 Feb 2010 16:05:21 -0500 Original-Received: from fencepost.gnu.org ([140.186.70.10]:54791) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1Nc3SR-0002RC-Qn; Mon, 01 Feb 2010 16:05:19 -0500 Original-Received: from rms by fencepost.gnu.org with local (Exim 4.69) (envelope-from ) id 1Nc3SR-0006Ap-FA; Mon, 01 Feb 2010 16:05:19 -0500 In-reply-to: <837hqyi1h7.fsf@gnu.org> (message from Eli Zaretskii on Sun, 31 Jan 2010 20:16:36 +0200) X-detected-operating-system: by monty-python.gnu.org: GNU/Linux 2.6 (newer, 3) X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:120794 gmane.emacs.bidi:495 Archived-At: > Maybe there SHOULD be a specified line length for this purpose. > (Perhaps fill-column? Or "use fill-column" could be one of the > settings.) nil could mean "use the window width". > > When the width is specified, not nil, then the right behavior > is to use that width even if it causes truncation. You are talking about introducing a new feature. That could be good, but for now I'd like to have a bidi display without new features. Ok, let's stick to the case where the window width controls it. > Horizontal scrolling should apply to the whole window contents > in a rigid fashion. But that cannot be done in this case, because the second line cannot be scrolled to the left without moving its first character A from the right margin. Horizontal scrolling does whatever we make it do. The question is what behavior is best. I'm saying that horizontal scrolling should move the window contents rigidly left or right, just as vertical scrolling moves the contents rigidly up or down. Perhaps with bidi text we should allow negative hscroll, in other words, scrolling the whole contents to the left of the usual position. The definition of hscroll is not the same as how we number columns for indentation purposes. Indentation is defined in terms of the order of text in the buffer. In a line that is entirely RTL, indentation needs to start from the right margin and work leftward. By contrast, horizontal scrolling is defined in terms of left and right, not forward and back.