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: Is there any particular reason `scroll-other-window' is written in C and not in ELisp? Date: Tue, 29 Dec 2015 20:23:21 +0200 Message-ID: <83wprxcdwm.fsf@gnu.org> References: <87y4cd8usv.fsf@mbork.pl> <83oad9dyzj.fsf@gnu.org> <87twn188bf.fsf@mbork.pl> Reply-To: Eli Zaretskii NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Trace: ger.gmane.org 1451413373 31565 80.91.229.3 (29 Dec 2015 18:22:53 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Tue, 29 Dec 2015 18:22:53 +0000 (UTC) Cc: Emacs-devel@gnu.org To: Marcin Borkowski Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Tue Dec 29 19:22:48 2015 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1aDyv1-0000Fb-Ec for ged-emacs-devel@m.gmane.org; Tue, 29 Dec 2015 19:22:47 +0100 Original-Received: from localhost ([::1]:49675 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aDyv0-00039I-L5 for ged-emacs-devel@m.gmane.org; Tue, 29 Dec 2015 13:22:46 -0500 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:40715) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aDyun-00039A-PJ for Emacs-devel@gnu.org; Tue, 29 Dec 2015 13:22:34 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aDyuj-0008B1-1F for Emacs-devel@gnu.org; Tue, 29 Dec 2015 13:22:33 -0500 Original-Received: from fencepost.gnu.org ([2001:4830:134:3::e]:60397) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aDyui-0008Ax-To; Tue, 29 Dec 2015 13:22:28 -0500 Original-Received: from 84.94.185.246.cable.012.net.il ([84.94.185.246]:4620 helo=HOME-C4E4A596F7) by fencepost.gnu.org with esmtpsa (TLS1.2:RSA_AES_128_CBC_SHA1:128) (Exim 4.82) (envelope-from ) id 1aDyug-0004GX-VE; Tue, 29 Dec 2015 13:22:28 -0500 In-reply-to: <87twn188bf.fsf@mbork.pl> (message from Marcin Borkowski on Tue, 29 Dec 2015 18:37:40 +0100) 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: 2.1.14 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-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:197127 Archived-At: > From: Marcin Borkowski > Cc: Emacs-devel@gnu.org > Date: Tue, 29 Dec 2015 18:37:40 +0100 > > > Because it needs to determine the new window-start which is a > > window-full above or below the current one, without assuming that all > > the lines have the same height in pixels. How do you do that in Lisp? > > (The current implementation simulates display.) > > Interesting, though I know too little about Emacs internals to fully > understand your answer. I thought it just does something like > > (save-excursion > (other-buffer) > (scroll-up)) > > Why my (probably naïve) implementation won't work? (You forget other-window-for-scrolling, but that's beside the point.) How would that help? The guts are in scroll-up, which is in C (as all the scrolling commands). Or are you saying that the bug is in the other-buffer part, rather than in the scrolling part? > > Sounds like a bug that should be reported. Not sure if it's in core > > Emacs or not, but please do report it with all the necessary details > > to whatever the guilty parties are. > > Not Emacs core, you're right. I'll file a bug report. Thanks.