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=AWL,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 1DACE1F4C0 for ; Wed, 23 Oct 2019 07:33:33 +0000 (UTC) Received: from neon.ruby-lang.org (localhost [IPv6:::1]) by neon.ruby-lang.org (Postfix) with ESMTP id 5E428120A7C; Wed, 23 Oct 2019 16:33:22 +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 8CC51120A5B for ; Wed, 23 Oct 2019 16:33:20 +0900 (JST) Received: by filter0043p3iad2.sendgrid.net with SMTP id filter0043p3iad2-1545-5DB00241-4E 2019-10-23 07:33:21.596853601 +0000 UTC m=+43982.141259396 Received: from herokuapp.com (unknown [52.91.158.104]) by ismtpd0070p1iad2.sendgrid.net (SG) with ESMTP id 8P_05dERQhur8PfF-fiM6g for ; Wed, 23 Oct 2019 07:33:21.497 +0000 (UTC) Date: Wed, 23 Oct 2019 07:33:21 +0000 (UTC) From: zverok.offline@gmail.com Message-ID: References: Mime-Version: 1.0 X-Redmine-MailingListIntegration-Message-Ids: 71085 X-Redmine-Project: ruby-trunk X-Redmine-Issue-Id: 16261 X-Redmine-Issue-Author: zverok X-Redmine-Sender: zverok 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?3be0g8093pjUjT94eiCA64csFDBI=2FmHQTWm54P5gda7fDA+L=2F4xk1MdB3JCOml?= =?us-ascii?Q?wN6jkBNEIyuzJvFXVTrKu6FlTY64JM9DrfgqWvz?= =?us-ascii?Q?JPBbPrZOtVwdLc1Qye+qZyTe5Fh9QtlTmshBiQ=2F?= =?us-ascii?Q?SvuPKprr=2F9u19eqqrpJa+yCDmJFGSz7uOeX3aKC?= =?us-ascii?Q?tcOCCJuBmLxieAXFVNzKi0pRmCQRMiSMTgg=3D=3D?= To: ruby-core@ruby-lang.org X-ML-Name: ruby-core X-Mail-Count: 95493 Subject: [ruby-core:95493] [Ruby master Feature#16261] Enumerable#each_tuple 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 zverok (Victor Shepelev). @duerst > What you want to do here is in many other languages done with `zip_with` I used `zip` only as a simplest way to construct an example. In our current codebase we have a fare share of internal methods defined with two pairs of braces, like `def similar?((word1, word2))`, because this allows us, for example, to say things like (imagine calculating some diffs): ```ruby diff_pairs.reject(&method(:similar?)).select(&method(:same_paragraph?)).map(&method(:calculate_closeness)) ``` In other places, we are still just rely on `map { |foo, bar, baz|`, `select` and so on. A very small amount of initial data of such chains is produced with `zip`, but even when it is, `zip_with` can't help with select/reject/group_by and other Enumerable methods. ---------------------------------------- Feature #16261: Enumerable#each_tuple https://bugs.ruby-lang.org/issues/16261#change-82264 * Author: zverok (Victor Shepelev) * Status: Open * Priority: Normal * Assignee: * Target version: ---------------------------------------- New method proposal. Prototype code: ```ruby module Enumerable def each_tuple return to_enum(__method__) unless block_given? each { |item| yield(*item) } # unpacking possible array into several args 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_tuple(&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_tuple.map(&:+) # => [5, 7, 9] ``` -- https://bugs.ruby-lang.org/