220 36482 <2830355.7vpS7njdV0@tjmaciei-mobl1> article Path: news.gmane.org!.POSTED!not-for-mail From: Thiago Macieira Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Interchangeable syntax for type forward declarations Date: Wed, 03 Jan 2018 17:35:13 -0200 Lines: 32 Approved: news@gmane.org Message-ID: <2830355.7vpS7njdV0@tjmaciei-mobl1> References: <848201ee-7402-4c4d-8a16-af610f945944@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 1515008017 26356 195.159.176.226 (3 Jan 2018 19:33:37 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Wed, 3 Jan 2018 19:33:37 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBCB4TK757YBRB7XAWTJAKGQEBEPHPPI@isocpp.org Wed Jan 03 20:33:33 2018 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-qt0-f199.google.com ([209.85.216.199]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1eWomy-00064y-OY for gclcip-std-proposals@m.gmane.org; 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[209.222.10.136]) by mx.google.com with ESMTPS id h138si373887qke.105.2018.01.03.11.35.26 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 03 Jan 2018 11:35:26 -0800 (PST) Received-SPF: pass (google.com: domain of thiago@macieira.org designates 209.222.10.136 as permitted sender) client-ip=209.222.10.136; Original-Received: from tjmaciei-mobl1.localnet (unknown [191.254.125.70]) by smtp.macieira.info (Postfix) with ESMTPSA id 9D12158E2 for ; Wed, 3 Jan 2018 11:35:25 -0800 (PST) In-Reply-To: <848201ee-7402-4c4d-8a16-af610f945944@isocpp.org> X-Original-Sender: thiago@macieira.org X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of thiago@macieira.org designates 209.222.10.136 as permitted sender) smtp.mailfrom=thiago@macieira.org Precedence: list Mailing-list: list std-proposals@isocpp.org; contact std-proposals+owners@isocpp.org List-ID: X-Spam-Checked-In-Group: std-proposals@isocpp.org 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:36482 Archived-At: On Wednesday, 3 January 2018 16:29:14 -02 Igor Baidiuk wrote: > There's one strange inconvenience in C++, which is forward declaring > certain type. Strange because it's really simple to fix IMO. > > 1. If you forward declare some type with struct/class/union, you're > required to use the same keyword when you define its body True for union, not true for struct or class. A union is quite a different beast from a struct/class. > 2. No way to forward-declare type alias. > > Proposal is very simple: > 1. Make struct/class interchangeable when forward-declaring anything. > Possibly, allow "typename" to be used in the same context Struct and class already ARE interchangeable. > 2. Allow to forward-declare type aliases the same way as normal types This I'd like to see. -- Thiago Macieira - thiago (AT) macieira.info - thiago (AT) kde.org Software Architect - Intel Open Source Technology Center -- 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. 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