From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Paul Eggert Newsgroups: gmane.emacs.devel Subject: Re: bignum branch Date: Fri, 3 Aug 2018 14:02:04 -0700 Message-ID: <42060bb4-3535-3b03-e007-0ae68134a30b@cs.ucla.edu> References: <87o9fbbw1t.fsf@tromey.com> <86in5jdj49.fsf@gmail.com> <83wotxaiwi.fsf@gnu.org> <86k1pxmvmx.fsf@gmail.com> <87efg4a9xc.fsf@tromey.com> <87a7qr8cz7.fsf@tromey.com> <86tvoy3je9.fsf@gmail.com> <86bmb0vbxf.fsf@gmail.com> <87k1pnfcg1.fsf@tromey.com> <86sh4b1833.fsf@gmail.com> <861sbgz3dm.fsf@gmail.com> <83a7q4ufxp.fsf@gnu.org> <86in4resc8.fsf@gmail.com> <831sbfvl11.fsf@gnu.org> <8636vv7ohh.fsf@gmail.com> <83y3dntwsw.fsf@gnu.org> <83wot7tkdh.fsf@gnu.org> <87y3dnyzkl.fsf@tromey.com> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Trace: blaine.gmane.org 1533330053 32475 195.159.176.226 (3 Aug 2018 21:00:53 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Fri, 3 Aug 2018 21:00:53 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 Cc: Andy Moreton , emacs-devel@gnu.org To: Tom Tromey , Eli Zaretskii Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Fri Aug 03 23:00:48 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 1flhBn-0008K3-9V for ged-emacs-devel@m.gmane.org; Fri, 03 Aug 2018 23:00:47 +0200 Original-Received: from localhost ([::1]:53059 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1flhDu-0001ap-05 for ged-emacs-devel@m.gmane.org; Fri, 03 Aug 2018 17:02:58 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:59773) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1flhDD-0001ai-Gt for emacs-devel@gnu.org; Fri, 03 Aug 2018 17:02:16 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1flhDC-0002Dd-RI for emacs-devel@gnu.org; Fri, 03 Aug 2018 17:02:15 -0400 Original-Received: from zimbra.cs.ucla.edu ([131.179.128.68]:46798) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1flhD7-00029g-Bh; Fri, 03 Aug 2018 17:02:09 -0400 Original-Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id 0449A16087B; Fri, 3 Aug 2018 14:02:07 -0700 (PDT) Original-Received: from zimbra.cs.ucla.edu ([127.0.0.1]) by localhost (zimbra.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id nl-TpxIUbP2H; Fri, 3 Aug 2018 14:02:06 -0700 (PDT) Original-Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id 1C8BD160885; Fri, 3 Aug 2018 14:02:06 -0700 (PDT) X-Virus-Scanned: amavisd-new at zimbra.cs.ucla.edu Original-Received: from zimbra.cs.ucla.edu ([127.0.0.1]) by localhost (zimbra.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id zJclirEW95pW; Fri, 3 Aug 2018 14:02:06 -0700 (PDT) Original-Received: from [192.168.1.29] (unknown [47.139.41.115]) by zimbra.cs.ucla.edu (Postfix) with ESMTPSA id 87B1F16087B; Fri, 3 Aug 2018 14:02:05 -0700 (PDT) In-Reply-To: <87y3dnyzkl.fsf@tromey.com> Content-Language: en-US X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [fuzzy] X-Received-From: 131.179.128.68 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:228138 Archived-At: On 08/03/2018 01:17 PM, Tom Tromey wrote: > I'm not sure what the semantics of NaN comparison are in Emacs. In > particular, this doesn't really make sense to me: > > (> 0 0.0e+NaN) => nil > (< 0 0.0e+NaN) => nil > (min 0 0.0e+NaN) => 0.0e+NaN > (min 0.0e+NaN 0) => 0.0e+NaN > (max 0 0.0e+NaN) => 0.0e+NaN > (max 0.0e+NaN 0) => 0.0e+NaN NaNs never compare numerically equal to, less than, or greater than any other floating-point value, even other NaNs. This is part of the IEEE standard. min and max propagate any NaNs they find. By the way, we've changed master so that eql now looks at NaN's significands. That is, (eql x y) now returns t if x and y are NaNs containing identical significands.