From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Drew Adams Newsgroups: gmane.emacs.devel Subject: RE: Three questions about pcase for Stefan Date: Sat, 23 Jan 2016 14:08:27 -0800 (PST) Message-ID: <4f92034b-858c-4c44-a51e-983da90a778a@default> References: <87r3h8zfd4.fsf@web.de> <56A3EF3E.3020502@cs.ucla.edu> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Trace: ger.gmane.org 1453586940 16405 80.91.229.3 (23 Jan 2016 22:09:00 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sat, 23 Jan 2016 22:09:00 +0000 (UTC) Cc: Emacs Development To: Paul Eggert , Stefan Monnier , Michael Heerdegen Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Sat Jan 23 23:08:48 2016 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 1aN6MR-0002wj-LU for ged-emacs-devel@m.gmane.org; Sat, 23 Jan 2016 23:08:47 +0100 Original-Received: from localhost ([::1]:58664 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aN6MR-0003Qt-3K for ged-emacs-devel@m.gmane.org; Sat, 23 Jan 2016 17:08:47 -0500 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:55946) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aN6MN-0003PR-HM for emacs-devel@gnu.org; Sat, 23 Jan 2016 17:08:44 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aN6MK-0008MO-B6 for emacs-devel@gnu.org; Sat, 23 Jan 2016 17:08:43 -0500 Original-Received: from userp1040.oracle.com ([156.151.31.81]:50968) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aN6MK-0008MK-3C for emacs-devel@gnu.org; Sat, 23 Jan 2016 17:08:40 -0500 Original-Received: from userv0022.oracle.com (userv0022.oracle.com [156.151.31.74]) by userp1040.oracle.com (Sentrion-MTA-4.3.2/Sentrion-MTA-4.3.2) with ESMTP id u0NM8S7S016913 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Sat, 23 Jan 2016 22:08:28 GMT Original-Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by userv0022.oracle.com (8.14.4/8.13.8) with ESMTP id u0NM8Rhl004509 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Sat, 23 Jan 2016 22:08:27 GMT Original-Received: from abhmp0010.oracle.com (abhmp0010.oracle.com [141.146.116.16]) by userv0122.oracle.com (8.14.4/8.13.8) with ESMTP id u0NM8QVT008724; Sat, 23 Jan 2016 22:08:26 GMT In-Reply-To: <56A3EF3E.3020502@cs.ucla.edu> X-Priority: 3 X-Mailer: Oracle Beehive Extensions for Outlook 2.0.1.9 (901082) [OL 12.0.6691.5000 (x86)] X-Source-IP: userv0022.oracle.com [156.151.31.74] X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.4.x-2.6.x [generic] X-Received-From: 156.151.31.81 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:198665 Archived-At: > > Testing equality of floating point numbers is very rarely correct. >=20 > Although it's rarely correct in programs written by newbies, it's > almost always correct in floating-point programs written by experts. Really? Care to give an expert example of what a `pcase' user would need to do? What users typically do for this, AFAIK, is to test that the given floating-point number is within a certain range. Even experts don't test equality using `equal' and such, AFAIK.