From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Original-To: poffice@blade.nagaokaut.ac.jp Delivered-To: poffice@blade.nagaokaut.ac.jp Received: from kankan.nagaokaut.ac.jp (kankan.nagaokaut.ac.jp [133.44.2.24]) by blade.nagaokaut.ac.jp (Postfix) with ESMTP id 96E7317C44B7 for ; Sun, 30 Oct 2011 07:19:24 +0900 (JST) Received: from funfun.nagaokaut.ac.jp (funfun.nagaokaut.ac.jp [133.44.2.201]) by kankan.nagaokaut.ac.jp (Postfix) with ESMTP id 827C5EA663D for ; Sun, 30 Oct 2011 07:09:41 +0900 (JST) Received: from localhost (localhost.nagaokaut.ac.jp [127.0.0.1]) by funfun.nagaokaut.ac.jp (Postfix) with ESMTP id A16BC8FC22 for ; Sun, 30 Oct 2011 07:09:41 +0900 (JST) X-Virus-Scanned: amavisd-new at funfun.nagaokaut.ac.jp Received: from funfun.nagaokaut.ac.jp ([127.0.0.1]) by localhost (funfun.nagaokaut.ac.jp [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id qKFOnvy5h2R6 for ; Sun, 30 Oct 2011 07:09:41 +0900 (JST) Received: from voscc.nagaokaut.ac.jp (voscc.nagaokaut.ac.jp [133.44.1.100]) by funfun.nagaokaut.ac.jp (Postfix) with ESMTP id 80F3F8FC21 for ; Sun, 30 Oct 2011 07:09:41 +0900 (JST) Received: from carbon.ruby-lang.org (carbon.ruby-lang.org [221.186.184.68]) by voscc.nagaokaut.ac.jp (Postfix) with ESMTP id 8D32495241F for ; Sun, 30 Oct 2011 07:09:40 +0900 (JST) Received: from beryllium.ruby-lang.org (beryllium.ruby-lang.org [127.0.0.1]) by carbon.ruby-lang.org (Postfix) with ESMTP id D21C13C21EB6B; Sun, 30 Oct 2011 07:09:38 +0900 (JST) Received: from fluorine.ruby-lang.org (www.rubyist.net [210.251.121.216]) by carbon.ruby-lang.org (Postfix) with ESMTP id E8E823C21F118 for ; Sun, 30 Oct 2011 07:09:30 +0900 (JST) Received: from ruby-lang.org (localhost [127.0.0.1]) by fluorine.ruby-lang.org (Postfix) with ESMTP id B6FC23ED2F for ; Sun, 30 Oct 2011 07:09:30 +0900 (JST) Delivered-To: ruby-core@ruby-lang.org Date: Sun, 30 Oct 2011 07:09:31 +0900 Posted: Sun, 30 Oct 2011 07:09:30 +0900 From: Alexey Muranov Reply-To: ruby-core@ruby-lang.org Subject: [ruby-core:40514] [ruby-trunk - Feature #5321] Introducing Numeric#exact? and Numeric#inexact? To: ruby-core@ruby-lang.org Message-Id: References: X-ML-Name: ruby-core X-Mail-Count: 40514 X-MLServer: fml [fml 4.0.3 release (20011202/4.0.3)]; post only (only members can post) X-ML-Info: If you have a question, send e-mail with the body "help" (without quotes) to the address ruby-core-ctl@ruby-lang.org; help= X-Mailer: Redmine X-Spam-Checker-Version: SpamAssassin 3.1.7-deb3 (2006-10-05) on carbon.ruby-lang.org X-Spam-Level: X-Spam-Status: No, score=0.1 required=7.0 tests=BAYES_50,CONTENT_TYPE_PRESENT, FORGED_RCVD_HELO,X_MAILER_PRESENT autolearn=disabled version=3.1.7-deb3 X-Redmine-Issue-Author: mrkn X-Redmine-Issue-Assignee: matz X-Redmine-Issue-Id: 5321 X-Redmine-Mailinglistintegration-Message-Ids: 10002 X-Redmine-Project: ruby-trunk Auto-Submitted: auto-generated X-Redmine-Site: Ruby Issue Tracking System X-Redmine-Host: redmine.ruby-lang.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Precedence: bulk List-Id: ruby-core.ruby-lang.org List-Software: fml [fml 4.0.3 release (20011202/4.0.3)] List-Post: List-Owner: List-Help: List-Unsubscribe: Issue #5321 has been updated by Alexey Muranov. I like this proposal. -Alexey. ---------------------------------------- Feature #5321: Introducing Numeric#exact? and Numeric#inexact? http://redmine.ruby-lang.org/issues/5321 Author: Kenta Murata Status: Open Priority: Normal Assignee: Yukihiro Matsumoto Category: Target version: Ruby has several numeric classes such as Integer. These classes are classified whether their instances represent numbers exactly. According to this, Integer and Rational are exact, and Float and BigDecimal are inexact because they're always including error. The exactness of a Complex depends on its real and imaginary parts. Now, Ruby's numeric classes doesn't provide predicators to investigate the exactness of their instances. So, if we want to examine whether a number is exactly zero, we must investigate the class of the number. I want simple way to examine the number exactness. I propose to introduce Numeric#exact? and/or Numeric#inexact? for resolving this inconvenience. -- http://redmine.ruby-lang.org