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: tabulated-list-init-header and glyphless-char-display Date: Sun, 10 Apr 2011 01:24:41 -0400 Message-ID: References: <83mxk0u0g7.fsf@gnu.org> <874o68zjhi.fsf@stupidchicken.com> <83k4f4twam.fsf@gnu.org> <8762qnxm44.fsf@stupidchicken.com> Reply-To: Eli Zaretskii NNTP-Posting-Host: lo.gmane.org X-Trace: dough.gmane.org 1302413099 12762 80.91.229.12 (10 Apr 2011 05:24:59 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Sun, 10 Apr 2011 05:24:59 +0000 (UTC) Cc: cyd@stupidchicken.com, emacs-devel@gnu.org To: Stefan Monnier Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Sun Apr 10 07:24:55 2011 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 1Q8n8o-0001T9-IC for ged-emacs-devel@m.gmane.org; Sun, 10 Apr 2011 07:24:54 +0200 Original-Received: from localhost ([127.0.0.1]:57023 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Q8n8n-0001eW-IJ for ged-emacs-devel@m.gmane.org; Sun, 10 Apr 2011 01:24:53 -0400 Original-Received: from [140.186.70.92] (port=41721 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Q8n8d-0001aP-GJ for emacs-devel@gnu.org; Sun, 10 Apr 2011 01:24:44 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Q8n8c-0006WB-H3 for emacs-devel@gnu.org; Sun, 10 Apr 2011 01:24:43 -0400 Original-Received: from fencepost.gnu.org ([140.186.70.10]:52866) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Q8n8c-0006W4-Af for emacs-devel@gnu.org; Sun, 10 Apr 2011 01:24:42 -0400 Original-Received: from eliz by fencepost.gnu.org with local (Exim 4.71) (envelope-from ) id 1Q8n8b-0003hN-CF; Sun, 10 Apr 2011 01:24:41 -0400 In-reply-to: (message from Stefan Monnier on Sun, 10 Apr 2011 00:59:21 -0300) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6 (newer, 3) X-Received-From: 140.186.70.10 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:138344 Archived-At: > From: Stefan Monnier > Cc: Eli Zaretskii , emacs-devel@gnu.org > Date: Sun, 10 Apr 2011 00:59:21 -0300 > > > Thanks. This doesn't quite do what I want, because (i) it applies to > > the entire buffer, when I only want it to apply to one particular glyph, > > and (ii) the char table's "fallback display" slot applies to all glyphs > > with no fonts, when I only want to handle two particular glyphs. > > Hmm... so IIUC we distinguish between "glyphless" and "without a font". > Where do we explain the difference between the two, and is there a good > reason to distinguish the two cases? No, "glyphless" and "without a font" are (and should be) synonyms. Except that on a text terminal, "without a font" means "cannot be encoded for the current terminal encoding". > > I propose introducing a `glyphless-char-display-default' text-property, > > which, if non-nil, overrides glyphless-char-display's "fallback display" > > slot locally. See attached patch, which seems to do the right thing. > > I think problem (i) above is not a real problem, so if we can fix (ii) > by changing glyphless-char-display we wouldn't need such a text property. What I had in mind was something much more lightweight: look at these characters' cells in glyphless-char-display (or use unencodable-char-position on a tty), and if that indicates that the characters cannot be displayed, use the surrogates. I see no need for a more general infrastructure for this case, as it is quite rare.