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#3452: 23.0.94; display Date: Mon, 08 Jun 2009 00:48:53 -0400 Message-ID: References: <877hzoogc1.fsf@cyd.mit.edu> Reply-To: Eli Zaretskii , 3452@emacsbugs.donarmstrong.com NNTP-Posting-Host: lo.gmane.org X-Trace: ger.gmane.org 1244437073 18836 80.91.229.12 (8 Jun 2009 04:57:53 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Mon, 8 Jun 2009 04:57:53 +0000 (UTC) Cc: cyd@stupidchicken.com To: Kenichi Handa , 3452@emacsbugs.donarmstrong.com Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Mon Jun 08 06:57:39 2009 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.50) id 1MDWvT-0006Ow-2g for geb-bug-gnu-emacs@m.gmane.org; Mon, 08 Jun 2009 06:57:39 +0200 Original-Received: from localhost ([127.0.0.1]:35051 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1MDWvO-0006wl-6e for geb-bug-gnu-emacs@m.gmane.org; Mon, 08 Jun 2009 00:57:34 -0400 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1MDWvI-0006rS-3q for bug-gnu-emacs@gnu.org; Mon, 08 Jun 2009 00:57:28 -0400 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1MDWvB-0006e4-SM for bug-gnu-emacs@gnu.org; Mon, 08 Jun 2009 00:57:26 -0400 Original-Received: from [199.232.76.173] (port=53707 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1MDWvB-0006dq-JM for bug-gnu-emacs@gnu.org; Mon, 08 Jun 2009 00:57:21 -0400 Original-Received: from rzlab.ucr.edu ([138.23.92.77]:46004) by monty-python.gnu.org with esmtps (TLS-1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1MDWvB-00074e-1u for bug-gnu-emacs@gnu.org; Mon, 08 Jun 2009 00:57:21 -0400 Original-Received: from rzlab.ucr.edu (rzlab.ucr.edu [127.0.0.1]) by rzlab.ucr.edu (8.14.3/8.14.3/Debian-5) with ESMTP id n584vJ3Z008730; Sun, 7 Jun 2009 21:57:19 -0700 Original-Received: (from debbugs@localhost) by rzlab.ucr.edu (8.14.3/8.14.3/Submit) id n584t4tF008146; Sun, 7 Jun 2009 21:55:04 -0700 X-Loop: owner@emacsbugs.donarmstrong.com Resent-From: Eli Zaretskii Resent-To: bug-submit-list@donarmstrong.com Resent-CC: Emacs Bugs Resent-Date: Mon, 08 Jun 2009 04:55:04 +0000 Resent-Message-ID: Resent-Sender: owner@emacsbugs.donarmstrong.com X-Emacs-PR-Message: followup 3452 X-Emacs-PR-Package: emacs X-Emacs-PR-Keywords: Original-Received: via spool by 3452-submit@emacsbugs.donarmstrong.com id=B3452.12444365437322 (code B ref 3452); Mon, 08 Jun 2009 04:55:04 +0000 Original-Received: (at 3452) by emacsbugs.donarmstrong.com; 8 Jun 2009 04:49:03 +0000 X-Spam-Bayes: score:0.5 Bayes not run. spammytokens:Tokens not available. hammytokens:Tokens not available. Original-Received: from fencepost.gnu.org (fencepost.gnu.org [140.186.70.10]) by rzlab.ucr.edu (8.14.3/8.14.3/Debian-5) with ESMTP id n584mth8007300 for <3452@emacsbugs.donarmstrong.com>; Sun, 7 Jun 2009 21:48:57 -0700 Original-Received: from eliz by fencepost.gnu.org with local (Exim 4.67) (envelope-from ) id 1MDWmz-0001XD-Tm; Mon, 08 Jun 2009 00:48:53 -0400 In-reply-to: (message from Kenichi Handa on Mon, 08 Jun 2009 10:51:14 +0900) X-detected-operating-system: by monty-python.gnu.org: GNU/Linux 2.6 (newer, 2) Resent-Date: Mon, 08 Jun 2009 00:57:26 -0400 X-BeenThere: bug-gnu-emacs@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Bug reports for GNU Emacs, the Swiss army knife of text editors" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.bugs:28548 Archived-At: > From: Kenichi Handa > Date: Mon, 08 Jun 2009 10:51:14 +0900 > Cc: 3452@emacsbugs.donarmstrong.com > Reply-To: Kenichi Handa , 3452@emacsbugs.donarmstrong.com > > On terminal, if a zero-width character doesn't follow a base > character, Emacs composes that character by prepending SPACE > hoping that the terminal treats that zero-width character as > zero-width too. So these characters should be currently displayed as SPACE? Is it a good idea to rely on the terminal in this situation? Do we know for a fact that many (most?) terminals indeed behave like that with zero-width characters? > > These characters are not supposed to be displayed at all, > > they have no meaningful glyphs to show them. They are just directives > > to the bidirectional display engines about how to convert logical > > order of characters to visual order. > > But as Emacs 23 doesn't support bidi, at least we should > make it edittable, don't we? Yes, definitely. (Btw, I think make them editable even when Emacs does support bidirectional editing.) > > Btw, I don't understand how these characters are related to > > compositions. They should not be composed with anything, they always > > stand for themselves. > > Currently they are not composed with any other surrounding > characters (but only with an artificially prepended SPACE), > so we can say that they stand for themselves. That's good, I think. > To conclude, I think there's not that much we can do for > this situation. I think the current behaviour of > gnome-terminal (displaying standalone U+202D as a space of > width 1) is a bug. If other terminals behave correctly, I would agree. But if not, perhaps we need to work around this, if possible. For example, we could have an entry in display tables for these characters.