220 32505 article Path: news.gmane.org!.POSTED!not-for-mail From: Ville Voutilainen Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Re: Allow Structured Binding Outside of Variable Declaration Date: Wed, 17 May 2017 01:49:09 +0300 Lines: 27 Approved: news@gmane.org Message-ID: References: <10b21241-b683-44d5-82ce-90681b2643a4@isocpp.org> <08ff73f1-6989-393e-ee4e-8158af2e7bed@honermann.net> <20170516164245.GA16348@fukushima.lysator.liu.se> 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 1494974954 15097 195.159.176.226 (16 May 2017 22:49:14 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Tue, 16 May 2017 22:49:14 +0000 (UTC) To: "ISO C++ Standard - Future Proposals" Original-X-From: std-proposals+bncBC5JHI7A7ALRBZUD53EAKGQEK7ACXMY@isocpp.org Wed May 17 00:49:10 2017 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-yw0-f198.google.com ([209.85.161.198]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1dAlH7-0003es-Pe for gclcip-std-proposals@m.gmane.org; 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[2607:f8b0:4003:c06::231]) by mx.google.com with ESMTPS id u19si75881otg.260.2017.05.16.15.49.10 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 16 May 2017 15:49:10 -0700 (PDT) Received-SPF: pass (google.com: domain of ville.voutilainen@gmail.com designates 2607:f8b0:4003:c06::231 as permitted sender) client-ip=2607:f8b0:4003:c06::231; Original-Received: by mail-oi0-x231.google.com with SMTP id h4so44019231oib.3 for ; Tue, 16 May 2017 15:49:10 -0700 (PDT) X-Received: by 10.157.68.199 with SMTP id p7mr255812otg.15.1494974949956; Tue, 16 May 2017 15:49:09 -0700 (PDT) Original-Received: by 10.157.17.253 with HTTP; Tue, 16 May 2017 15:49:09 -0700 (PDT) In-Reply-To: X-Original-Sender: ville.voutilainen@gmail.com X-Original-Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com; spf=pass (google.com: domain of ville.voutilainen@gmail.com designates 2607:f8b0:4003:c06::231 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:32505 Archived-At: On 17 May 2017 at 01:43, Zhihao Yuan wrote: >> > How about this >> > >> > for (TupleLike [x, y] : something) { ... } >> > >> > Where TupleLike is a concept. >> >> How does that help me specify the concrete types of the bindings? > > > It does type-check, as same as you putting > > static_assert(is_same_v); > > in the loop. > > But it doesn't change the type object of the > underlying object, or the type of the bindings. I need to use some weird concept to check that the type of x is A? -- 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/CAFk2RUYeKYjhmX9fVwDaV7zJRLxAmJx%3DhSsgPWLMFJD%2BwTW3MQ%40mail.gmail.com. .