From mboxrd@z Thu Jan 1 00:00:00 1970 Path: main.gmane.org!not-for-mail From: Richard Stallman Newsgroups: gmane.emacs.devel Subject: Re: Face color changes Date: Mon, 03 Jan 2005 22:36:40 -0500 Message-ID: References: <01c4ec3a$Blat.v2.2.2$24b7cc60@zahav.net.il> <87oegf5974.fsf@jurta.org> <01c4ed1a$Blat.v2.2.2$4b8d4aa0@zahav.net.il> <87k6r1r7bb.fsf@jurta.org> <87u0q5ruqx.fsf@confusibombus.emacswiki.org> <20041230012747.GA29490@fencepost> Reply-To: rms@gnu.org NNTP-Posting-Host: deer.gmane.org X-Trace: sea.gmane.org 1104810290 4012 80.91.229.6 (4 Jan 2005 03:44:50 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Tue, 4 Jan 2005 03:44:50 +0000 (UTC) Cc: emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Tue Jan 04 04:44:40 2005 Return-path: Original-Received: from lists.gnu.org ([199.232.76.165]) by deer.gmane.org with esmtp (Exim 3.35 #1 (Debian)) id 1Clfce-0004ak-00 for ; Tue, 04 Jan 2005 04:44:40 +0100 Original-Received: from localhost ([127.0.0.1] helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.33) id 1Clfnp-0000ll-5D for ged-emacs-devel@m.gmane.org; Mon, 03 Jan 2005 22:56:13 -0500 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.33) id 1Clfng-0000lY-Sp for emacs-devel@gnu.org; Mon, 03 Jan 2005 22:56:05 -0500 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.33) id 1Clfng-0000l9-3o for emacs-devel@gnu.org; Mon, 03 Jan 2005 22:56:04 -0500 Original-Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.33) id 1Clfng-0000l6-25 for emacs-devel@gnu.org; Mon, 03 Jan 2005 22:56:04 -0500 Original-Received: from [199.232.76.164] (helo=fencepost.gnu.org) by monty-python.gnu.org with esmtp (Exim 4.34) id 1ClfbA-0005Og-BQ for emacs-devel@gnu.org; Mon, 03 Jan 2005 22:43:08 -0500 Original-Received: from rms by fencepost.gnu.org with local (Exim 4.34) id 1ClfUu-0007gk-GT; Mon, 03 Jan 2005 22:36:40 -0500 Original-To: Kevin Rodgers In-reply-to: (message from Kevin Rodgers on Mon, 03 Jan 2005 11:17:36 -0700) 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: main.gmane.org gmane.emacs.devel:31785 X-Report-Spam: http://spam.gmane.org/gmane.emacs.devel:31785 > Yes, but I think it is a drastic thing to do--to discard all the other > conditional alternatives that the user doesn't even know about. The > user probably meant the customization to replace the behavior he saw. It's drastic, but it's basically the same thing that happens for variables. It is partly similar and partly different. Variables don't have specs with conditions, they just have initial value forms. The fact that specs represent the alternatives and their conditions in a declarative way makes it natural not to discard them. Since faces have conditional specs, should variables have specs (vs. just lisp object values) as well? This technique is useful for faces because (1) there is a limited set of conditions that you might want to test and (2) users can plausibly run in different backgrounds and terminals even on the same system. It is clear we cannot usefully apply the specs technique to variables generally. Perhaps there are certain variables for which the technique is applicable.