220 41413 article Path: news.gmane.org!.POSTED.blaine.gmane.org!not-for-mail From: Matthew Woehlke Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Overloading `using` for temporary scopes Date: Tue, 29 Jan 2019 11:42:15 -0500 Approved: news@gmane.org Message-ID: References: <41a2bed6-6738-cd11-0037-9a471f8a75d5@gmail.com> Reply-To: std-proposals@isocpp.org Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Injection-Info: blaine.gmane.org; posting-host="blaine.gmane.org:195.159.176.226"; logging-data="175492"; mail-complaints-to="usenet@blaine.gmane.org" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.4.0 To: std-proposals@isocpp.org, David Brown Original-X-From: std-proposals+bncBC37LBFWUIFBB2UEYLRAKGQE7GXI36Q@isocpp.org Tue Jan 29 17:42:22 2019 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-qt1-f200.google.com ([209.85.160.200]) by blaine.gmane.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.89) (envelope-from ) id 1goWSq-000jUj-AA for gclcip-std-proposals@m.gmane.org; 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[66.194.253.20]) by smtp.googlemail.com with ESMTPSA id j138sm54178071qke.65.2019.01.29.08.42.16 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 29 Jan 2019 08:42:16 -0800 (PST) Openpgp: preference=signencrypt In-Reply-To: Content-Language: en-US X-Original-Sender: mwoehlke.floss@gmail.com X-Original-Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=LG5HmA+O; spf=pass (google.com: domain of mwoehlke.floss@gmail.com designates 209.85.220.41 as permitted sender) smtp.mailfrom=mwoehlke.floss@gmail.com; dmarc=pass (p=NONE sp=QUARANTINE 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:41413 Archived-At: On 29/01/2019 09.26, David Brown wrote: > On 28/01/2019 17:20, Matthew Woehlke wrote: >> I often wish C++ had the equivalent of Python's `with` [...] I >> wonder if there would be any perceived value in having a dedicated >> syntax for this? I'm thinking [e.g.]: >> >> with (auto x = expr()) >> with (expr()) > > Basically, what you want is to be able to give "expr()" a name so that > it stays in scope, but you don't want to give it a name because it isn't > something you are going to use. Yes. But *sometimes*. Eventually I think we will get a way to declare an anonymous variable; too many people have wanted it for too long. The reason my proposal might be interesting is because it is one syntax that allows *either* naming the temporary or not naming it. -- Matthew -- 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/de706d53-f3c1-1810-ff61-cc6cc4f40270%40gmail.com. .