220 33712 article Path: news.gmane.org!.POSTED!not-for-mail From: Ville Voutilainen Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Re: A more advanced switch Date: Wed, 9 Aug 2017 15:09:35 +0300 Lines: 30 Approved: news@gmane.org Message-ID: References: <5a36b655-b2a9-4be2-8599-465810cfd1b3@isocpp.org> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" X-Trace: blaine.gmane.org 1502280578 26165 195.159.176.226 (9 Aug 2017 12:09:38 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Wed, 9 Aug 2017 12:09:38 +0000 (UTC) Cc: costelnistor12@gmail.com To: "ISO C++ Standard - Future Proposals" Original-X-From: std-proposals+bncBC5JHI7A7ALRBAHXVPGAKGQE4Y3Y4BQ@isocpp.org Wed Aug 09 14:09:32 2017 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-ua0-f197.google.com ([209.85.217.197]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1dfPnn-0006UF-JZ for gclcip-std-proposals@m.gmane.org; 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[2607:f8b0:400c:c08::243]) by mx.google.com with ESMTPS id k11si2362535uai.401.2017.08.09.05.09.36 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 09 Aug 2017 05:09:36 -0700 (PDT) Received-SPF: pass (google.com: domain of ville.voutilainen@gmail.com designates 2607:f8b0:400c:c08::243 as permitted sender) client-ip=2607:f8b0:400c:c08::243; Original-Received: by mail-ua0-x243.google.com with SMTP id k43so3761342uaf.1 for ; Wed, 09 Aug 2017 05:09:36 -0700 (PDT) X-Received: by 10.159.37.70 with SMTP id 64mr4872848uaz.195.1502280576212; Wed, 09 Aug 2017 05:09:36 -0700 (PDT) Original-Received: by 10.103.103.65 with HTTP; Wed, 9 Aug 2017 05:09:35 -0700 (PDT) In-Reply-To: <5a36b655-b2a9-4be2-8599-465810cfd1b3@isocpp.org> X-Original-Sender: ville.voutilainen@gmail.com X-Original-Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=J64xEjry; spf=pass (google.com: domain of ville.voutilainen@gmail.com designates 2607:f8b0:400c:c08::243 as permitted sender) smtp.mailfrom=ville.voutilainen@gmail.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=gmail.com Precedence: list Mailing-list: list std-proposals@isocpp.org; contact std-proposals+owners@isocpp.org List-ID: X-Google-Group-Id: 399137483710 List-Post: , List-Help: , List-Archive: List-Subscribe: , List-Unsubscribe: , Xref: news.gmane.org gmane.comp.lang.c++.isocpp.proposals:33712 Archived-At: On 9 August 2017 at 14:55, wrote: > I'd like to see a generalization of switch, allowing it to be used with for > example std::string (view). > > std::string s; > > switch (s) > { > case "A": > case "B": > default: > } > > No syntax updates necessary. That's not a switch, that's an if-else chain masquerading as a switch. I would strongly suggest adding a pattern-matching mechanism and leaving switch alone; switch has semantics that don't fit into general matching, and other expectations that a general matching mechanism doesn't have, including recommendations against using switch because switch does fall-through and a general matching mechanism probably shouldn't. -- You received this message because you are subscribed to the Google Groups "ISO C++ Standard - Future Proposals" group. To unsubscribe from this group and stop receiving emails from it, send an email to std-proposals+unsubscribe@isocpp.org. To post to this group, send email to std-proposals@isocpp.org. To view this discussion on the web visit https://groups.google.com/a/isocpp.org/d/msgid/std-proposals/CAFk2RUYqZVo775jwQP%2BAGiqf3JRq8yNxB1Ru_b74YPa-qJfooA%40mail.gmail.com. .