220 5224 article Path: news.gmane.org!not-for-mail From: Richard Smith Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: brace-intialization and C++14 generalized lambda capture Date: Tue, 25 Jun 2013 12:07:16 -0700 Lines: 50 Approved: news@gmane.org Message-ID: References: <10c2a060-47cc-47bc-9114-c599c4986f4f@isocpp.org> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable X-Trace: ger.gmane.org 1372187238 28593 80.91.229.3 (25 Jun 2013 19:07:18 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Tue, 25 Jun 2013 19:07:18 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBDVNBJG4YAIBBZOUU6HAKGQEV5CBM3Y@isocpp.org Tue Jun 25 21:07:19 2013 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-vb0-f71.google.com ([209.85.212.71]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1UrYaE-0001ON-MO for gclcip-std-proposals@m.gmane.org; Tue, 25 Jun 2013 21:07:18 +0200 Original-Received: by mail-vb0-f71.google.com with SMTP id f12sf17141179vbg.6 for ; Tue, 25 Jun 2013 12:07:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=x-beenthere:mime-version:sender:in-reply-to:references:date :message-id:subject:from:to:x-original-sender :x-original-authentication-results:reply-to:precedence:mailing-list :list-id:x-google-group-id:list-post:list-help:list-archive :list-subscribe:list-unsubscribe:content-type :content-transfer-encoding; bh=Vggb4TEopgKC6xmx9PGnZcQjzkuI73KqtFBxPexE2lY=; b=nnrVCKhxS9DZP3LdBsmiR1ZpxG+aPT2FCA6crGbIuV9dnIfsoSDLxMGpSwgzpMZAo8 FJIOJJ/m3I+pMZY7VJvfrn4cIEYPmT12HM59WI+bRbyLL7YtRTC+VQc/vqYS8VG/lUzq X8em1HMszQjQZ3Od8TrmZ9PCsAw5p+1Sv3vrMLLOK1KYn2fteznKUX9EZcMR9E69fhpk 4la2JH8OVMa7ej817DsSTrNr/ecbL1i0elZh1mTEeirJQV8fHQIGUWfkOiIZqo6p/BQo RgUsiNhFf96A0m+DWxvR89gauObaUzMLHzXfS8Lnx+ZFtTzwYjC4YKdnKHmIQkCpKhwX X-Received: by 10.236.110.168 with SMTP id u28mr212857yhg.32.1372187237853; Tue, 25 Jun 2013 12:07:17 -0700 (PDT) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.49.35.50 with SMTP id e18ls123185qej.99.gmail; Tue, 25 Jun 2013 12:07:17 -0700 (PDT) X-Received: by 10.220.164.138 with SMTP id e10mr288416vcy.27.1372187237135; Tue, 25 Jun 2013 12:07:17 -0700 (PDT) Original-Received: from mail-vb0-x230.google.com (mail-vb0-x230.google.com [2607:f8b0:400c:c02::230]) by mx.google.com with ESMTPS id tq4si6662355vdc.105.2013.06.25.12.07.17 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Tue, 25 Jun 2013 12:07:17 -0700 (PDT) Received-SPF: pass (google.com: domain of metafoo@gmail.com designates 2607:f8b0:400c:c02::230 as permitted sender) client-ip=2607:f8b0:400c:c02::230; Original-Received: by mail-vb0-f48.google.com with SMTP id w15so9930719vbf.35 for ; Tue, 25 Jun 2013 12:07:17 -0700 (PDT) X-Received: by 10.58.216.97 with SMTP id op1mr243273vec.60.1372187236985; Tue, 25 Jun 2013 12:07:16 -0700 (PDT) Original-Sender: metafoo@gmail.com Original-Received: by 10.58.125.73 with HTTP; Tue, 25 Jun 2013 12:07:16 -0700 (PDT) In-Reply-To: <10c2a060-47cc-47bc-9114-c599c4986f4f@isocpp.org> X-Original-Sender: richard@metafoo.co.uk X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of metafoo@gmail.com designates 2607:f8b0:400c:c02::230 as permitted sender) smtp.mail=metafoo@gmail.com; dkim=pass header.i=@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:5224 Archived-At: On Tue, Jun 25, 2013 at 11:44 AM, wrote: > The C++14 CD (N3690) at the paragraph $5.1.2/11, says: > For every init-capture a non-static data member named by the identifier o= f > the init-capture is declared in > the closure type. This member is not a bit-field and not mutable. The typ= e > of that member corresponds to > the type of a hypothetical variable declaration of the form =93auto > init-capture ;=94, except that the variable > name (i.e., the identifier of the init-capture) is replaced by a unique > identifier. > > As I understand this means that the type of member x declared in lambda > capture as [x{std::move(uniq_ptr)}] () {} will be the same as would be fo= r > the expression auto x{std::move(unique_ptr)}. That means that type of x > would be std::initializer_list> (assuming that type = of > unique_ptr is std::unique_ptr). in contrast the original prposal > contains of lambda example [ x { move(x) }, y =3D transform(y, z), foo, b= ar, > baz ] { ... }, which suggest that type of x would be std::unique_ptr= .. > > I am understanding the wording correctly? If so was this change made on > purpose? We discussed this in core. We didn't want init-captures to behave differently from auto variable initialization, but there was a feeling that auto variable initialization from a braced-init-list should be fixed to not produce a std::initializer_list type here. We are expecting at least one national body comment requesting a fix for this, so there's a good chance that auto-deduction from initializer lists will change in the C++14 FDIS to not give an initializer_list type in the above case. --=20 ---=20 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 e= mail to std-proposals+unsubscribe@isocpp.org. To post to this group, send email to std-proposals@isocpp.org. Visit this group at http://groups.google.com/a/isocpp.org/group/std-proposa= ls/. .