220 21346 article Path: news.gmane.org!not-for-mail From: =?UTF-8?Q?Agust=c3=adn_K-ballo_Berg=c3=a9?= Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Re: Conversion from lvalue to rvalue Date: Tue, 6 Oct 2015 09:51:58 -0300 Lines: 42 Approved: news@gmane.org Message-ID: References: <31dedac5-7d51-402c-946e-0555c925f70d@isocpp.org> <116a66a2-90ea-4269-ac85-3432ff7094b0@isocpp.org> <42447957-4276-4f59-89b6-ab4be37c47c6@isocpp.org> <2C19913E-B6BC-423D-8570-939C3A573CDF@gmail.com> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable X-Trace: ger.gmane.org 1444135933 26981 80.91.229.3 (6 Oct 2015 12:52:13 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Tue, 6 Oct 2015 12:52:13 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBD2JZ7PP7QERB4MHZ6YAKGQETESIT7Y@isocpp.org Tue Oct 06 14:52:04 2015 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-qg0-f69.google.com ([209.85.192.69]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1ZjRit-0004qb-A5 for gclcip-std-proposals@m.gmane.org; Tue, 06 Oct 2015 14:52:03 +0200 Original-Received: by qgev79 with SMTP id v79sf224690207qge.0 for ; Tue, 06 Oct 2015 05:52:02 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:message-id:subject:to:references:from:date :user-agent:mime-version:in-reply-to:content-type :content-transfer-encoding:x-original-sender :x-original-authentication-results:reply-to:precedence:mailing-list :list-id:x-spam-checked-in-group:list-post:list-help:list-archive :list-subscribe:list-unsubscribe; bh=hN9VqUP5mxsC6rx1m4DphfZyBWtHfPDj73YtQpqBygo=; b=COBFWgSOsAbT+cgoKM4tRrI48+L6fGq4sZl5kYqZn1SNXc8VcjqjnYSVMMGLayV/5I kTIGpBZPACt0MpqPfW5KifB5BQo9sHERSgsvClGFV+5tofht4zDlkzkNg1FTHakf9dbQ 8ZJkFg+RNr1Z9Id+anl3G2eKNPBU1FoSQb0uaWhQJnap4ID99zwlCJhVxA11H3d8KKxR grYT81yhaGOLSrVEVrbwdxoUjoJ/PKu63R0C+iW+6JN0tr4GqxqCcJLGtWNf8sjxtOaG e6ZWiSIuPce5bPhvxEuogleiW91ZyxCNFZprAU5Abti4dgx X-Gm-Message-State: ALoCoQnDZ4fhbVA6yL6LekDyknmkFhfdkqu0fNhxYz9COLDzdoOpKqRN7u0gha7cWC5Mx483jlBi X-Received: by 10.129.145.68 with SMTP id i65mr29025829ywg.1.1444135922299; Tue, 06 Oct 2015 05:52:02 -0700 (PDT) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.182.251.198 with SMTP id zm6ls1557853obc.33.gmail; Tue, 06 Oct 2015 05:52:01 -0700 (PDT) X-Received: by 10.60.46.168 with SMTP id w8mr21695074oem.82.1444135921212; Tue, 06 Oct 2015 05:52:01 -0700 (PDT) Original-Received: from BLU004-OMC1S23.hotmail.com (blu004-omc1s23.hotmail.com. [65.55.116.34]) by mx.google.com with ESMTPS id j8si16088574obz.28.2015.10.06.05.52.01 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Tue, 06 Oct 2015 05:52:01 -0700 (PDT) Received-SPF: pass (google.com: domain of kaballo86@hotmail.com designates 65.55.116.34 as permitted sender) client-ip=65.55.116.34; Original-Received: from BLU436-SMTP228 ([65.55.116.8]) by BLU004-OMC1S23.hotmail.com over TLS secured channel with Microsoft SMTPSVC(7.5.7601.23008); Tue, 6 Oct 2015 05:52:00 -0700 X-TMN: [Pa34X24f3ALBpJflRG3h/EIhsA0PivIT] X-Originating-Email: [kaballo86@hotmail.com] User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.3.0 In-Reply-To: <2C19913E-B6BC-423D-8570-939C3A573CDF@gmail.com> X-OriginalArrivalTime: 06 Oct 2015 12:51:59.0395 (UTC) FILETIME=[CA12C730:01D10035] X-Original-Sender: kaballo86@hotmail.com X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of kaballo86@hotmail.com designates 65.55.116.34 as permitted sender) smtp.mailfrom=kaballo86@hotmail.com; dmarc=pass (p=NONE dis=NONE) header.from=hotmail.com 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:21346 Archived-At: On 10/6/2015 4:34 AM, David Krauss wrote: > >> On 2015=E2=80=9310=E2=80=9306, at 9:37 AM, Agust=C3=ADn K-ballo Berg=C3= =A9 >> > wrote: >> >> This would do wasteful copies from rvalues. If you look at 30.2.6 >> [thread.decaycopy] you'll see it's defined as: >> >> template decay_t decay_copy(T&& v) >> { return std::forward(v); } >> >> I guess `auto` would do too. > > decay_copy would always perform a copy, from an lvalue, xvalue, or prvalu= e. > > auto{} would allow copy elision for prvalue operands. It would copy > lvalue, xvalue, and derived-type prvalues. I don't know where this comes from. Since it says `auto` I'll assume is=20 about it being an option too. I meant this: template auto decay_copy(T&& v) { return std::forward(v); } Regards, --=20 Agust=C3=ADn K-ballo Berg=C3=A9.- http://talesofcpp.fusionfenix.com --=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/. .