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 3EF131F5AE for ; Thu, 23 Jul 2020 18:43:06 +0000 (UTC) Received: from neon.ruby-lang.org (localhost [IPv6:::1]) by neon.ruby-lang.org (Postfix) with ESMTP id D8B5C120B4A; Fri, 24 Jul 2020 03:42:35 +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 53477120B49 for ; Fri, 24 Jul 2020 03:42:33 +0900 (JST) Received: by filterdrecv-p3mdw1-75c584b9c6-dv7cm with SMTP id filterdrecv-p3mdw1-75c584b9c6-dv7cm-19-5F19DA34-40 2020-07-23 18:43:00.616782417 +0000 UTC m=+1904058.832330640 Received: from herokuapp.com (unknown) by ismtpd0091p1iad2.sendgrid.net (SG) with ESMTP id 2AJViYCfSFOn6v9YMjtz6g for ; Thu, 23 Jul 2020 18:43:00.557 +0000 (UTC) Date: Thu, 23 Jul 2020 18:43:00 +0000 (UTC) From: marcandre-ruby-core@marc-andre.ca Message-ID: References: Mime-Version: 1.0 X-Redmine-MailingListIntegration-Message-Ids: 75093 X-Redmine-Project: ruby-master X-Redmine-Issue-Tracker: Feature X-Redmine-Issue-Id: 17043 X-Redmine-Issue-Author: delonnewman X-Redmine-Sender: marcandre 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?6=2FIMxCQLDposcQf5wmbDAtfaKduBAO0bKyhL3BGZtMQ5q7K2TvpbN6A7JIyt9E?= =?us-ascii?Q?aOZ+w38gaN=2FSFXYwoja5naSYXRJzYzQaZgxAUxl?= =?us-ascii?Q?SdqV+K+x2TVEWB9WxPiJGiNOyVEDLzlL53zsvI7?= =?us-ascii?Q?cY5K1UGATBeMmYCTe=2Fm4hnODkl=2FbPQ385h3b6YQ?= =?us-ascii?Q?qo1QRJREYn8psdxawBkNYWykoefWtAXpBIjR3fO?= =?us-ascii?Q?EppA2d66VZV1YkFxhFNoB6mqcf75iQUBARL04H?= To: ruby-core@ruby-lang.org X-ML-Name: ruby-core X-Mail-Count: 99303 Subject: [ruby-core:99303] [Ruby master Feature#17043] Invokable module for custom Proc-like objects 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 #17043 has been updated by marcandre (Marc-Andre Lafortune). Status changed from Feedback to Rejected > But, it'd be great to be able to treat sets as predicate functions Note that since Ruby 2.5, `Set#===` is an alias for `include?`, so you can do `ary.grep(Set[...])` for example. > I'm curious if an officially blessed "Invokable" module might be a useful thing for the standard library. Most of the standard library is being made available as separate gems (or removed altogether), so we're basically trying to reduce the standard library, not extend it. Thanks for enquiring though. ---------------------------------------- Feature #17043: Invokable module for custom Proc-like objects https://bugs.ruby-lang.org/issues/17043#change-86691 * Author: delonnewman (Delon Newman) * Status: Rejected * Priority: Normal ---------------------------------------- Ruby beautifully integrates Functional and Object-Oriented Programming, and there's more moving in the direction of supporting Functional Programming. A generalization of the Proc interface would enable users to integrate functional approach into their classic OOP design patterns. One of the obvious examples would be "Command" objects. Also, generic structures, which Ruby has great support for. Hash now has `to_proc`. But, it'd be great to be able to treat sets as predicate functions. I've put together a prototype that I've found useful in my own work here: https://github.com/delonnewman/invokable. It works like Enumerable; it can be included in any class that implements a `call` method. Then you get `to_proc`, `curry`, `<<` and `>>` for right and left composition, and `memoize`. More could be added. If you include `Invokable::Command`, you can treat your "Command" object as an automatically curried function. -- https://bugs.ruby-lang.org/