From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Stefan Monnier Newsgroups: gmane.emacs.devel Subject: Re: Unary / Date: Thu, 15 Oct 2015 14:45:21 -0400 Message-ID: References: <87pp0gweri.fsf@fencepost.gnu.org> <22047.37539.943171.429065@turnbull.sk.tsukuba.ac.jp> <877fmouyt3.fsf@gnu.org> <87d1wgwclb.fsf@fencepost.gnu.org> <871tcww7q9.fsf@fencepost.gnu.org> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: ger.gmane.org 1444934782 777 80.91.229.3 (15 Oct 2015 18:46:22 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Thu, 15 Oct 2015 18:46:22 +0000 (UTC) Cc: "Stephen J. Turnbull" , emacs-devel@gnu.org To: David Kastrup Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Thu Oct 15 20:46:09 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 1ZmnXT-0003MK-KW for ged-emacs-devel@m.gmane.org; Thu, 15 Oct 2015 20:46:07 +0200 Original-Received: from localhost ([::1]:49178 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZmnXS-00086d-ML for ged-emacs-devel@m.gmane.org; Thu, 15 Oct 2015 14:46:06 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:58576) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZmnXG-00080r-TT for emacs-devel@gnu.org; Thu, 15 Oct 2015 14:45:55 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZmnXF-0003dG-TC for emacs-devel@gnu.org; Thu, 15 Oct 2015 14:45:54 -0400 Original-Received: from mercure.iro.umontreal.ca ([132.204.24.67]:35833) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZmnX9-0003ay-OT; Thu, 15 Oct 2015 14:45:48 -0400 Original-Received: from hidalgo.iro.umontreal.ca (hidalgo.iro.umontreal.ca [132.204.27.50]) by mercure.iro.umontreal.ca (Postfix) with ESMTP id C68C986115; Thu, 15 Oct 2015 14:45:45 -0400 (EDT) Original-Received: from lechon.iro.umontreal.ca (lechon.iro.umontreal.ca [132.204.27.242]) by hidalgo.iro.umontreal.ca (Postfix) with ESMTP id 44DC81E5B9F; Thu, 15 Oct 2015 14:45:22 -0400 (EDT) Original-Received: by lechon.iro.umontreal.ca (Postfix, from userid 20848) id 0691FB43A9; Thu, 15 Oct 2015 14:45:21 -0400 (EDT) In-Reply-To: <871tcww7q9.fsf@fencepost.gnu.org> (David Kastrup's message of "Thu, 15 Oct 2015 16:02:06 +0200") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.0.50 (gnu/linux) X-DIRO-MailScanner-Information: Please contact the ISP for more information X-DIRO-MailScanner: Found to be clean X-DIRO-MailScanner-SpamCheck: n'est pas un polluriel, SpamAssassin (score=-2.82, requis 5, autolearn=not spam, ALL_TRUSTED -2.82, MC_TSTLAST 0.00) X-DIRO-MailScanner-From: monnier@iro.umontreal.ca X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6.x X-Received-From: 132.204.24.67 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:191677 Archived-At: > (- 3) is not the same as (- 3 0) but as (- 0 3), just like (/ 3.0) is > not the same as (/ 3.0 1.0) but as (/ 1.0 3.0). Indeed, the - has the same asymmetry, but it seems that "unary -" is much more commonly found operator than "unary /". And I'm pretty sure there are many uses of (- X) out there, so we can't really get rid of it. Stefan