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-ASN: AS4713 221.184.0.0/13 X-Spam-Status: No, score=-2.7 required=3.0 tests=BAYES_00,DKIM_ADSP_CUSTOM_MED, FORGED_GMAIL_RCVD,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED, SPF_HELO_NONE,SPF_PASS shortcircuit=no autolearn=no 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 E7EEA1F5A6 for ; Mon, 11 Nov 2019 23:43:45 +0000 (UTC) Received: from neon.ruby-lang.org (localhost [IPv6:::1]) by neon.ruby-lang.org (Postfix) with ESMTP id 8E4E2120A96; Tue, 12 Nov 2019 08:43:36 +0900 (JST) Received: from o1678948x4.outbound-mail.sendgrid.net (o1678948x4.outbound-mail.sendgrid.net [167.89.48.4]) by neon.ruby-lang.org (Postfix) with ESMTPS id 724DB120A85 for ; Tue, 12 Nov 2019 08:43:35 +0900 (JST) Received: by filter0144p3mdw1.sendgrid.net with SMTP id filter0144p3mdw1-9908-5DC9F228-2C 2019-11-11 23:43:36.605571606 +0000 UTC m=+17010.027393763 Received: from herokuapp.com (unknown [35.171.185.2]) by ismtpd0048p1iad2.sendgrid.net (SG) with ESMTP id 4j3wHvv-SKacG1qT6ttoew for ; Mon, 11 Nov 2019 23:43:36.489 +0000 (UTC) Date: Mon, 11 Nov 2019 23:43:36 +0000 (UTC) From: shevegen@gmail.com Message-ID: References: Mime-Version: 1.0 X-Redmine-MailingListIntegration-Message-Ids: 71431 X-Redmine-Project: ruby-trunk X-Redmine-Issue-Id: 16341 X-Redmine-Issue-Author: Nondv X-Redmine-Sender: shevegen 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?6lbdtOg4RDRLuxD00eQtQKgoNAsge5d4xND7cbMQd0wskmLoM2iwsvFkQ3zqXU?= =?us-ascii?Q?Bg2tmLQwMcNJQdKN7UYqtm7PSKmpsDaT4lyWG0R?= =?us-ascii?Q?QoQPIR4m5pSHjuYh1dmWfw3ALD7xkN4eCd0tYhx?= =?us-ascii?Q?6DFkK6v3F1oAwhkAc5XNkZppe6qKOm0xTVTgL6z?= =?us-ascii?Q?O3W9DF7Wt2T5OkKaE7iflNWM7+vNQz2CVPg=3D=3D?= To: ruby-core@ruby-lang.org X-ML-Name: ruby-core X-Mail-Count: 95804 Subject: [ruby-core:95804] [Ruby master Feature#16341] Proposal: Set#to_proc 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 #16341 has been updated by shevegen (Robert A. Heiler). > this change is just nice-to-have sugar. I don't expect it to > become a thing. The ruby core team often points out that having good use cases may help a proposal; and of course avoiding other problems such as backwards-incompatibility or such. Your initial comment is quite sparse, so zverok sort of got you to explain more lateron. ;) I am not really using ruby in a functional-centric manner nor do I know clojure (aside from superficial glances), but to me personally I am not completely sure if the use case has been explained. Unless it was only syntactic sugar of course. ---------------------------------------- Feature #16341: Proposal: Set#to_proc https://bugs.ruby-lang.org/issues/16341#change-82626 * Author: Nondv (Dmitry Non) * Status: Open * Priority: Normal * Assignee: * Target version: ---------------------------------------- ``` ruby class Set def to_proc -> (x) { include?(x) } # or method(:include?).to_proc end end ``` Usage: ```ruby require 'set' banned_numbers = Set[0, 5, 7, 9] (1..10).reject(&banned_numbers) # ===> [1, 2, 3, 4, 6, 8, 10] ``` -- https://bugs.ruby-lang.org/