From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-Status: No, score=-3.9 required=3.0 tests=AWL,BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED, SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from neon.ruby-lang.org (neon.ruby-lang.org [221.186.184.75]) by dcvr.yhbt.net (Postfix) with ESMTP id 67BA91F5AE for ; Sat, 1 Aug 2020 02:18:28 +0000 (UTC) Received: from neon.ruby-lang.org (localhost [IPv6:::1]) by neon.ruby-lang.org (Postfix) with ESMTP id 4E034120B7E; Sat, 1 Aug 2020 11:17:56 +0900 (JST) Received: from xtrwkhkc.outbound-mail.sendgrid.net (xtrwkhkc.outbound-mail.sendgrid.net [167.89.16.28]) by neon.ruby-lang.org (Postfix) with ESMTPS id 68C9E120B7B for ; Sat, 1 Aug 2020 11:17:54 +0900 (JST) Received: by filterdrecv-p3iad2-d8cc6d457-vqmvz with SMTP id filterdrecv-p3iad2-d8cc6d457-vqmvz-18-5F24D0EE-1 2020-08-01 02:18:22.018338552 +0000 UTC m=+202207.598472736 Received: from herokuapp.com (unknown) by geopod-ismtpd-3-1 (SG) with ESMTP id VMxhbXaYQ3WG18CUqnqasw for ; Sat, 01 Aug 2020 02:18:22.008 +0000 (UTC) Date: Sat, 01 Aug 2020 02:18:22 +0000 (UTC) From: merch-redmine@jeremyevans.net Message-ID: References: Mime-Version: 1.0 X-Redmine-MailingListIntegration-Message-Ids: 75255 X-Redmine-Project: ruby-master X-Redmine-Issue-Tracker: Bug X-Redmine-Issue-Id: 17098 X-Redmine-Issue-Author: chrisseaton X-Redmine-Sender: jeremyevans0 X-Mailer: Redmine X-Redmine-Host: bugs.ruby-lang.org X-Redmine-Site: Ruby Issue Tracking System X-Auto-Response-Suppress: All Auto-Submitted: auto-generated X-SG-EID: =?us-ascii?Q?RVE3t853K5scBhbmJHUzZTFFeVC=2FZSUmHZ0Dc+26wcEi2CTgsF1oz0wTSSxGGN?= =?us-ascii?Q?BIJMegBFMLihI6vzBL9b24WPoNlxs89H6Ld8NM3?= =?us-ascii?Q?uriKtmosg26cstCMxj6L9PMJZYG1DlQVHw5NQLu?= =?us-ascii?Q?ChAta3rfR64byU14bqlbYGo3GaapYr3klzWk8D7?= =?us-ascii?Q?M3KNJrqQ2UyN=2FppSGdRtFQe2Gj2prud2vvZPvYH?= =?us-ascii?Q?aW5RtlszLJDsNEZl4=3D?= To: ruby-core@ruby-lang.org X-ML-Name: ruby-core X-Mail-Count: 99427 Subject: [ruby-core:99427] [Ruby master Bug#17098] Float#negative? reports negative zero as not negative X-BeenThere: ruby-core@ruby-lang.org X-Mailman-Version: 2.1.15 Precedence: list Reply-To: Ruby developers List-Id: Ruby developers List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: ruby-core-bounces@ruby-lang.org Sender: "ruby-core" Issue #17098 has been updated by jeremyevans0 (Jeremy Evans). I disagree. By that logic, positive float zero should be positive (it isn't), and since `-0.0 == 0.0` both should report as negative and positive, which is a contradiction. ---------------------------------------- Bug #17098: Float#negative? reports negative zero as not negative https://bugs.ruby-lang.org/issues/17098#change-86879 * Author: chrisseaton (Chris Seaton) * Status: Open * Priority: Normal * Backport: 2.5: UNKNOWN, 2.6: UNKNOWN, 2.7: UNKNOWN ---------------------------------------- Is this intended behaviour? ``` irb(main):001:0> neg_zero = -0.0 => -0.0 irb(main):002:0> neg_zero.negative? => false irb(main):003:0> neg_zero < 0 => false ``` It happens because `Numeric#negative?` uses `< 0`. My understanding of IEEE floating point is that negative zero is not less than zero, but I think it should still report as negative. -- https://bugs.ruby-lang.org/