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 ED02C19C0061 for ; Tue, 10 Nov 2015 12:15:50 +0900 (JST) Received: from voscc.nagaokaut.ac.jp (voscc.nagaokaut.ac.jp [133.44.1.100]) by kankan.nagaokaut.ac.jp (Postfix) with ESMTP id 89296B5D858 for ; Tue, 10 Nov 2015 12:45:24 +0900 (JST) Received: from neon.ruby-lang.org (neon.ruby-lang.org [221.186.184.75]) by voscc.nagaokaut.ac.jp (Postfix) with ESMTP id C639518CC7B6 for ; Tue, 10 Nov 2015 12:45:24 +0900 (JST) Received: from [221.186.184.76] (localhost [IPv6:::1]) by neon.ruby-lang.org (Postfix) with ESMTP id 4906912047D; Tue, 10 Nov 2015 12:45:23 +0900 (JST) X-Original-To: ruby-core@ruby-lang.org Delivered-To: ruby-core@ruby-lang.org Received: from o2.heroku.sendgrid.net (o2.heroku.sendgrid.net [67.228.50.55]) by neon.ruby-lang.org (Postfix) with ESMTPS id B10B8120461 for ; Tue, 10 Nov 2015 12:45:16 +0900 (JST) DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=sendgrid.me; h=from:to:references:subject:mime-version:content-type:content-transfer-encoding:list-id; s=smtpapi; bh=lh6v6pw2EP44YOlAKzf/VSKupUg=; b=R4YlLynQXG+mDDn9eh bsIJ35Xcp6KmW7yexpOHnbhWSvrKJvzyxhA/oJFaqzxVRNOka+B1VXzIM4X71hpg 0bZtclWeCwxlnNqqT+yGkJ762LSCGYnc3O6Qqfh9KNoFfkRvuQh4L2mP09EIydU1 UdeLw76qpHmiILecmiJ6ciWzw= Received: by filter-358.sjc1.sendgrid.net with SMTP id filter-358.3129.564168465 2015-11-10 03:45:10.107215133 +0000 UTC Received: from herokuapp.com (ec2-184-72-159-37.compute-1.amazonaws.com [184.72.159.37]) by ismtpd0004p1iad1.sendgrid.net (SG) with ESMTP id adDcW1J6RUSxwrS2N3yXCw Tue, 10 Nov 2015 03:45:09.993 +0000 (UTC) Date: Tue, 10 Nov 2015 03:45:09 +0000 From: akr@fsij.org To: ruby-core@ruby-lang.org Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Redmine-MailingListIntegration-Message-Ids: 46067 X-Redmine-Project: ruby-trunk X-Redmine-Issue-Id: 10984 X-Redmine-Issue-Author: olivierlacan X-Redmine-Issue-Assignee: akr X-Redmine-Sender: akr 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: ync6xU2WACa70kv/Ymy4QrNMhiuLXJG8OTL2vJD1yS6tLo/sTZgbuaKKtXwqoC8z6dWEsC9ssBJA4S O98y1JFh40LS4iaW3NqoePq34DW/xJRlmnuonCmk9xs3XVmT+MYfHOcMh5qV7ar9SsnMrOvF2yF1WH GUzg3x2NYe+EgjE= X-ML-Name: ruby-core X-Mail-Count: 71427 Subject: [ruby-core:71427] [Ruby trunk - Feature #10984] Hash#contain? to check whether hash contains other hash 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: , Errors-To: ruby-core-bounces@ruby-lang.org Sender: "ruby-core" Issue #10984 has been updated by Akira Tanaka. Nobuyoshi Nakada wrote: > If we'll introduce `Hash#<=` and `Hash#>=`, then `Hash#<` and `Hash#>` too? Maybe. Usefulness of `Hash#<` and `Hash#>` is not discussed well, though. > `Hash` will include `Comparable` with `Hash#<=>`? No. It is clearly stated by matz. ``` % ruby -e ' class Hash def <=(other) self.merge(other) == other end def >=(other) self.merge(other) == self end def <(other) self <= other && self != other end def >(other) self >= other && self != other end end hs = [{a:1, b:2}, {a:1, b:2, c:3}] ops = %w[<= >= < >] ops.each {|op| hs.each {|h1| hs.each {|h2| puts "#{h1} #{op} #{h2} = #{h1.send(op, h2)}" } } } ' {:a=>1, :b=>2} <= {:a=>1, :b=>2} = true {:a=>1, :b=>2} <= {:a=>1, :b=>2, :c=>3} = true {:a=>1, :b=>2, :c=>3} <= {:a=>1, :b=>2} = false {:a=>1, :b=>2, :c=>3} <= {:a=>1, :b=>2, :c=>3} = true {:a=>1, :b=>2} >= {:a=>1, :b=>2} = true {:a=>1, :b=>2} >= {:a=>1, :b=>2, :c=>3} = false {:a=>1, :b=>2, :c=>3} >= {:a=>1, :b=>2} = true {:a=>1, :b=>2, :c=>3} >= {:a=>1, :b=>2, :c=>3} = true {:a=>1, :b=>2} < {:a=>1, :b=>2} = false {:a=>1, :b=>2} < {:a=>1, :b=>2, :c=>3} = true {:a=>1, :b=>2, :c=>3} < {:a=>1, :b=>2} = false {:a=>1, :b=>2, :c=>3} < {:a=>1, :b=>2, :c=>3} = false {:a=>1, :b=>2} > {:a=>1, :b=>2} = false {:a=>1, :b=>2} > {:a=>1, :b=>2, :c=>3} = false {:a=>1, :b=>2, :c=>3} > {:a=>1, :b=>2} = true {:a=>1, :b=>2, :c=>3} > {:a=>1, :b=>2, :c=>3} = false ``` ---------------------------------------- Feature #10984: Hash#contain? to check whether hash contains other hash https://bugs.ruby-lang.org/issues/10984#change-54795 * Author: Olivier Lacan * Status: Open * Priority: Normal * Assignee: Akira Tanaka ---------------------------------------- Comparing hashes seems like a common practice but there currently isn't a method to ask a hash instance whether it includes another hash instance. The most intuitive method to reach for would be `Hash#include?` but it is in fact an alias to `Hash#has_key?` What I'm looking for can be achieved with: ~~~ class Hash def contain?(other) self.merge(other) == self end end ~~~ Here's a simple demo of `#contain?` in use: ~~~ { a: true, b: false }.contain?({ a: true}) # => true { a: true, b: false }.contain?({ b: false}) # => true { a: true, b: false }.contain?({ a: false}) # => false { a: true, b: false }.contain?({ c: true}) # => false ~~~ One important note is that this method is *not checking for nested hash matches*. This may need to be addressed when the parameters include a nested hash perhaps. Thanks to Terence Lee's help, nobu created a patch for this feature last year. I've only modified the name of the method from [his original patch](https://gist.github.com/nobu/dfe8ba14a48fc949f2ed) and attached it to this issue. ---Files-------------------------------- Hash#contain_.patch (2.22 KB) -- https://bugs.ruby-lang.org/