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=-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 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 9DA6D1F463 for ; Thu, 28 Nov 2019 08:16:02 +0000 (UTC) Received: from neon.ruby-lang.org (localhost [IPv6:::1]) by neon.ruby-lang.org (Postfix) with ESMTP id BD159120B6A; Thu, 28 Nov 2019 17:15:48 +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 2F74B120B62 for ; Thu, 28 Nov 2019 17:15:45 +0900 (JST) Received: by filter0051p3iad2.sendgrid.net with SMTP id filter0051p3iad2-17578-5DDF8236-29 2019-11-28 08:15:50.862325688 +0000 UTC m=+721572.513471923 Received: from herokuapp.com (unknown [3.87.7.191]) by ismtpd0069p1iad2.sendgrid.net (SG) with ESMTP id r7CymiP0S82ELXZ6vFMqTg for ; Thu, 28 Nov 2019 08:15:50.851 +0000 (UTC) Date: Thu, 28 Nov 2019 08:15:50 +0000 (UTC) From: matz@ruby.or.jp Message-ID: References: Mime-Version: 1.0 X-Redmine-MailingListIntegration-Message-Ids: 71652 X-Redmine-Project: ruby-trunk X-Redmine-Issue-Id: 16261 X-Redmine-Issue-Author: zverok X-Redmine-Sender: matz 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?bXEIHGfdFwsIlBTndiToCp=2Fmc2rfxRD2sZAksRKJIHWAR5a0WCtUdMz95F=2F5rT?= =?us-ascii?Q?y=2FwaXDhezLX0RQiz72t0UrNjsS+0q4yJOM0HjkZ?= =?us-ascii?Q?AUYRxaMlSYUlBcp3XeEVgoRaWRCB1sLP2aElcMb?= =?us-ascii?Q?xCPUK=2F2RCwrTgtDriJokkuyA2Ho2Bmr+SBPpT8d?= =?us-ascii?Q?AZnVOr2kJgrsk+hshLSGxQvW7DFZ2p3BX9Q=3D=3D?= To: ruby-core@ruby-lang.org X-ML-Name: ruby-core X-Mail-Count: 96015 Subject: [ruby-core:96015] [Ruby master Feature#16261] Enumerable#each_splat and Enumerator#splat 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 #16261 has been updated by matz (Yukihiro Matsumoto). Status changed from Open to Rejected As far as I understand, the code with the proposal `[1, 2, 3].zip([4, 5, 6]).each_tuple.map(&:+)` can be written as following with numbered parameters: ```ruby [1, 2, 3].zip([4, 5, 6]).map{_1 + _2} ``` which is quite plain and shorter. So I reject the idea for the time being. Maybe we will revisit the idea once we re-introduce the method reference operator in the future. Matz. ---------------------------------------- Feature #16261: Enumerable#each_splat and Enumerator#splat https://bugs.ruby-lang.org/issues/16261#change-82856 * Author: zverok (Victor Shepelev) * Status: Rejected * Priority: Normal * Assignee: * Target version: ---------------------------------------- **UPD:** After discussion in comments, method names changed to "splat"-based. New methods proposal. Prototype code: ```ruby module Enumerable def each_splat return to_enum(__method__) unless block_given? each_entry { |item| yield(*item) } # unpacking possible array into several args end end class Enumerator def splat return to_enum(:splat) unless block_given? each_entry { |item| yield(*item) } end end ``` Supposed documentation/explanation: > For enumerable with Array items, passes all items in the block provided as a separate arguments. t could be useful if the provided block has lambda semantics, e.g. doesn't unpack arguments automatically. For example: ```ruby files = ["README.md", "LICENSE.txt", "Contributing.md"] content = [fetch_readme, fetch_license, fetch_contributing] # somehow make a content for the files files.zip(content).each_splat(&File.:write) # writes to each file its content ``` > When no block passed, returns enumerator of the tuples: ```ruby [1, 2, 3].zip([4, 5, 6]).each_splat.map(&:+) # => [5, 7, 9] ``` -- https://bugs.ruby-lang.org/