From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: Questions about text properties Date: Sun, 21 Oct 2018 15:17:50 +0300 Message-ID: <83r2gjtrwx.fsf@gnu.org> References: <87pnw46l2z.fsf@portable.galex-713.eu> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Trace: blaine.gmane.org 1540124209 32718 195.159.176.226 (21 Oct 2018 12:16:49 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Sun, 21 Oct 2018 12:16:49 +0000 (UTC) Cc: emacs-devel@gnu.org To: "Garreau\, Alexandre" Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Sun Oct 21 14:16:44 2018 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1gECey-0008Q7-4d for ged-emacs-devel@m.gmane.org; Sun, 21 Oct 2018 14:16:44 +0200 Original-Received: from localhost ([::1]:58643 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gECh4-0007cE-CH for ged-emacs-devel@m.gmane.org; Sun, 21 Oct 2018 08:18:54 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:33257) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gECgM-0007by-3R for emacs-devel@gnu.org; Sun, 21 Oct 2018 08:18:10 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gECgI-0002pL-VY for emacs-devel@gnu.org; Sun, 21 Oct 2018 08:18:10 -0400 Original-Received: from fencepost.gnu.org ([2001:4830:134:3::e]:57129) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gECgI-0002pC-R0; Sun, 21 Oct 2018 08:18:06 -0400 Original-Received: from [176.228.60.248] (port=1809 helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:RSA_AES_256_CBC_SHA1:256) (Exim 4.82) (envelope-from ) id 1gECgI-0000RR-Cs; Sun, 21 Oct 2018 08:18:06 -0400 In-reply-to: <87pnw46l2z.fsf@portable.galex-713.eu> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 2001:4830:134:3::e X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.21 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 Original-Sender: "Emacs-devel" Xref: news.gmane.org gmane.emacs.devel:230539 Archived-At: > From: "Garreau\, Alexandre" > Date: Sun, 21 Oct 2018 05:21:40 +0200 > > – how about adding stuff to a *value* of property, be it a list, or > anything that could inherit, such as an alist, a keymap, etc.? it > seems there are no functions for that; Not sure I understand why you need something special: modifying a Lisp value, whether to add something or otherwise, is rather trivial, no? > – why are properties rear-sticky by default rather than the opposite? Because the other alternative is rarely needed. E.g., if you modify a string that has a face, you want the appended characters to inherit the same face. By contrast, inserting before the string rarely needs such inheritance. > – why is there only a mouse-face property, rather than a hover, click, > pressed, active, focus, etc. The usual reason: low demand and/or low motivation to develop features that are in low demand. Another possible reason is that at least some of those (click and press -- what's the difference, btw?) you can have already, by using the 'keymap' property, and perhaps a few others. > – why can it only affects face rather than other properties so that to > extend its behavior? By "it" you mean, mouse-face? Because it's a face. > – sometimes most text properties can take a hook (that will be called > lazily to compute a valid value), sometimes not (like for a display > prop space); Not sure what this is about. In general, only functions have hooks, not properties. How about a couple of examples? > — is the recenter thing about overlays related to the fact buffers are > implemented with a buffer gap, or is it just something similar to > fasten stuff? It makes overlay access faster.