From mboxrd@z Thu Jan 1 00:00:00 1970 Path: main.gmane.org!not-for-mail From: storm@cua.dk (Kim F. Storm) Newsgroups: gmane.emacs.devel Subject: Re: compute-motion inconsistency Date: 23 Jul 2004 14:56:32 +0200 Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Message-ID: References: NNTP-Posting-Host: deer.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: sea.gmane.org 1090587407 8711 80.91.224.253 (23 Jul 2004 12:56:47 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Fri, 23 Jul 2004 12:56:47 +0000 (UTC) Cc: emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Fri Jul 23 14:56:39 2004 Return-path: Original-Received: from lists.gnu.org ([199.232.76.165]) by deer.gmane.org with esmtp (Exim 3.35 #1 (Debian)) id 1BnzbK-0005DR-00 for ; Fri, 23 Jul 2004 14:56:38 +0200 Original-Received: from localhost ([127.0.0.1] helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.33) id 1BnzeC-0005ke-Qm for ged-emacs-devel@m.gmane.org; Fri, 23 Jul 2004 08:59:36 -0400 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.33) id 1Bnze1-0005jL-45 for emacs-devel@gnu.org; Fri, 23 Jul 2004 08:59:25 -0400 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.33) id 1Bnzdy-0005iT-A2 for emacs-devel@gnu.org; Fri, 23 Jul 2004 08:59:23 -0400 Original-Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.33) id 1Bnzdy-0005iJ-6t for emacs-devel@gnu.org; Fri, 23 Jul 2004 08:59:22 -0400 Original-Received: from [212.88.64.25] (helo=mail-relay.sonofon.dk) by monty-python.gnu.org with smtp (Exim 4.34) id 1Bnzau-0002Qh-21 for emacs-devel@gnu.org; Fri, 23 Jul 2004 08:56:12 -0400 Original-Received: (qmail 1225 invoked from network); 23 Jul 2004 12:55:56 -0000 Original-Received: from unknown (HELO kfs-l.imdomain.dk.cua.dk) (213.83.150.2) by 0 with SMTP; 23 Jul 2004 12:55:56 -0000 Original-To: David Kastrup In-Reply-To: Original-Lines: 78 User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.3.50 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: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: main.gmane.org gmane.emacs.devel:25902 X-Report-Spam: http://spam.gmane.org/gmane.emacs.devel:25902 David Kastrup writes: > storm@cua.dk (Kim F. Storm) writes: > > > > IIRC, the ones which do this correctly (the second category) I > > have fixed myself while working on redisplay over the past years. > > I somewhat doubt that they do this correctly. I think that things > differ again if one customizes the fringes off. Well, if you configure the fringes off, you don't get any continuation or truncation glyphs on window based display. Tough! I thought about ways to recognize this, but the window based redisplay code does not handle continuation/truncation glyphs, so it's a bit tricky, and I decided against using (my) time on this. I suggest to let the people who turn off the fringes: a) accept these inconveniences, b) implement this themselves. > > In my opinion, it is a complete mistake not to leave the continuation > glyph mess actually to compute-motion itself as soon as the WINDOW > parameter is actually present. Actually, that's what I suggested to do. > > > For backwards compatibility, I suggest the following change to > > compute-motion: > > > > If "width" equals (1- (window-width)) on a window system, > > automatically use (window-width) instead. > > > > If "width" equals (window-width) on a non-window system, > > automatically subtract 1 (for the continuation glyph). > > That's not "compatibility", that is madness. I don't think that this > sort of change, which makes things utterly incomprehensible and > unpredictable for the sake of some backward compatibility idea, is > warranted. So your "solution" is to do the following: If "width" equals (1- (window-width)) on a window system, use that. [This behave incorrectly, as it does now]. If "width" equals (window-width) on a window system, use that. [This is what I suggusted to do]. If "width" equals (window-width) on a non-window system, automatically subtract 1 (for the continuation glyph). [This is what I suggusted to do]. If "width" equals (1- (window-width)) on a non-window system, automatically subtract 1 (for the continuation glyph). [This will behave incorrectly, whereas it work correctly now, and is the documented required parameter]. So where my suggested "madness" behaves correctly for all 4 cases, your change will fix one case, leave one case unsolved, and break one case -- the very case that was previously documented as the required parameter value. Maybe that's not madness in your book, but it definitely is not "compatibility" in my book. > I prefer an incompatible change where just window-width can be used, > always. We had inconsistent behavior and usage before, tough. I don't prefer any specific solution -- that's why I asked: WDYT? -- Kim F. Storm http://www.cua.dk