From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED.blaine.gmane.org!not-for-mail From: Alan Mackenzie Newsgroups: gmane.emacs.devel Subject: Re: [Emacs-diffs] master 29d1c72: Introduce new value t for compilation-context-lines to eliminate scrolling Date: Sun, 25 Aug 2019 19:06:37 +0000 Message-ID: <20190825190637.GE4724@ACM> References: <20190825102322.19558.22771@vcs0.savannah.gnu.org> <20190825102323.5080620CD5@vcs0.savannah.gnu.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Injection-Info: blaine.gmane.org; posting-host="blaine.gmane.org:195.159.176.226"; logging-data="236500"; mail-complaints-to="usenet@blaine.gmane.org" User-Agent: Mutt/1.10.1 (2018-07-13) Cc: emacs-devel@gnu.org To: Stefan Monnier Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Sun Aug 25 21:08:47 2019 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([209.51.188.17]) by blaine.gmane.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1i1xsc-000zOc-7q for ged-emacs-devel@m.gmane.org; Sun, 25 Aug 2019 21:08:46 +0200 Original-Received: from localhost ([::1]:46506 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i1xsb-0007nv-5N for ged-emacs-devel@m.gmane.org; Sun, 25 Aug 2019 15:08:45 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:34503) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i1xqb-0005yr-DN for emacs-devel@gnu.org; Sun, 25 Aug 2019 15:06:42 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1i1xqa-0004og-8c for emacs-devel@gnu.org; Sun, 25 Aug 2019 15:06:41 -0400 Original-Received: from colin.muc.de ([193.149.48.1]:59329 helo=mail.muc.de) by eggs.gnu.org with smtp (Exim 4.71) (envelope-from ) id 1i1xqa-0004oP-2v for emacs-devel@gnu.org; Sun, 25 Aug 2019 15:06:40 -0400 Original-Received: (qmail 3944 invoked by uid 3782); 25 Aug 2019 18:13:50 -0000 Original-Received: from acm.muc.de (p2E5D5A8B.dip0.t-ipconnect.de [46.93.90.139]) by colin.muc.de (tmda-ofmipd) with ESMTP; Sun, 25 Aug 2019 20:13:49 +0200 Original-Received: (qmail 8553 invoked by uid 1000); 25 Aug 2019 19:06:37 -0000 Content-Disposition: inline In-Reply-To: X-Delivery-Agent: TMDA/1.1.12 (Macallan) X-Primary-Address: acm@muc.de X-detected-operating-system: by eggs.gnu.org: FreeBSD 9.x [fuzzy] X-Received-From: 193.149.48.1 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.23 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:239557 Archived-At: Hello, Stefan. On Sun, Aug 25, 2019 at 14:39:46 -0400, Stefan Monnier wrote: > Hi Alan, > I have a few questions abut your change. > > * lisp/progmodes/compile.el (compilation-context-lines): Add the new value t. > > (compilation-set-window): Amend to handle compilation-context-lines being t. > > (overlay-arrow-overlay): New variable holding an overlay with before-string > > property "=>". > 1- Why `overlay-arrow-overlay` without a `compilation-` prefix? It goes together with overlay-arrow-string, and overlay-arrow-position. > 2- Why insert a prefix string (an "inserted arrow") instead of using > a "regular overwriting arrow"? Because the overwriting arrow would obliterate the first two characters of the file name. I actually tried this first, and it wasn't satisfactory. This contrasts with another use of the overwriting arrow in edebug, where (usually) only WS gets overwritten, and it is important not to disturb the visible indentation. > 3- Why link the choice of inserted-arrow vs regular-overwriting-arrow to > compilation-context-lines specifically? Simplicity: mainly confusion on my part as just to where all the bits of the new code would have to go if the "insertion" arrow were to be made a general feature. If the new mechanism is a success, it should be easier then to make it more general. > -- Stefan "maybe part of my confusion is that I'm not sufficiently > familiar with the behavior when there's no left-fringe" That behaviour involves scrolling the current line to the top of the buffer, and several years of that had exceeded my irritation threshold. I usually run on a Linux tty, where there's no possibility of a fringe. -- Alan Mackenzie (Nuremberg, Germany).