220 4745 <51A7039F.20007@gmail.com> article Path: news.gmane.org!not-for-mail From: Anthony Williams Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: N3558 :A standardized representation of Asynchronous operation Date: Thu, 30 May 2013 08:45:35 +0100 Lines: 62 Approved: news@gmane.org Message-ID: <51A7039F.20007@gmail.com> References: <519F9E48.7050700@wanadoo.fr> <51A0B7C3.40109@wanadoo.fr> <51A6EFE6.4030407@wanadoo.fr> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable X-Trace: ger.gmane.org 1369899942 21560 80.91.229.3 (30 May 2013 07:45:42 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Thu, 30 May 2013 07:45:42 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBD65DK5LTQNBBIUHTSGQKGQEE6TSKGI@isocpp.org Thu May 30 09:45:41 2013 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-ea0-f200.google.com ([209.85.215.200]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1UhxYJ-0002KD-SN for gclcip-std-proposals@m.gmane.org; Thu, 30 May 2013 09:45:39 +0200 Original-Received: by mail-ea0-f200.google.com with SMTP id b15sf7765255eae.3 for ; Thu, 30 May 2013 00:45:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=x-beenthere:message-id:date:from:user-agent:mime-version:to:subject :references:in-reply-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=EJNtMnWsNnUShKU0OPbGK0/ZXlR4jJrM04/ff/MgGFs=; b=CgJLEtdJo2Tm/2xPkEycMug76fblVhUq/8BdpaWVCMRI4AK58z2q/+iqVzEpNQmBVA DDrGI57+KgQp0rm241XAQIxofsuOn3HFQS800PewOjmPIxd1WfJTTOpOJUc6ZbcTvMwG WRGwD3unaqOx0j0MWqNe9EKTmy8WDGMbXbJ4L/DfQ4DLytYGef2r1lgQTgFnLLqW6TMX OHmFgDkALKVynSphfarbT0RLZD1GUbrhyW9v9Vtr7k9ITvDCrvmzD0DDE3KCv+tUO0Sv V0xB29C9htbq0lONhaxDbQGvUAI6ouqLc3Y2zvNAYt3hyrFYENyROwIsUeVU4DNCpepA X-Received: by 10.180.189.74 with SMTP id gg10mr2099177wic.4.1369899938399; Thu, 30 May 2013 00:45:38 -0700 (PDT) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.180.36.77 with SMTP id o13ls170603wij.22.gmail; Thu, 30 May 2013 00:45:37 -0700 (PDT) X-Received: by 10.194.110.201 with SMTP id ic9mr3340216wjb.47.1369899937481; Thu, 30 May 2013 00:45:37 -0700 (PDT) Original-Received: from mail-wi0-x22c.google.com (mail-wi0-x22c.google.com [2a00:1450:400c:c05::22c]) by mx.google.com with ESMTPS id v4si7762699wjq.175.2013.05.30.00.45.37 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Thu, 30 May 2013 00:45:37 -0700 (PDT) Received-SPF: pass (google.com: domain of anthony.ajw@gmail.com designates 2a00:1450:400c:c05::22c as permitted sender) client-ip=2a00:1450:400c:c05::22c; Original-Received: by mail-wi0-f172.google.com with SMTP id m6so4247976wiv.17 for ; Thu, 30 May 2013 00:45:37 -0700 (PDT) X-Received: by 10.194.47.240 with SMTP id g16mr3338221wjn.43.1369899937355; Thu, 30 May 2013 00:45:37 -0700 (PDT) Original-Received: from ?IPv6:2a01:7e00:e000:2a::9001? ([2a01:7e00:e000:2a::9001]) by mx.google.com with ESMTPSA id fz8sm36086352wib.2.2013.05.30.00.45.35 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Thu, 30 May 2013 00:45:36 -0700 (PDT) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130510 Thunderbird/17.0.6 In-Reply-To: <51A6EFE6.4030407@wanadoo.fr> X-Original-Sender: anthony.ajw@gmail.com X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of anthony.ajw@gmail.com designates 2a00:1450:400c:c05::22c as permitted sender) smtp.mail=anthony.ajw@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:4745 Archived-At: On 30/05/13 07:21, Vicente J. Botet Escriba wrote: > Le 25/05/13 15:08, Vicente J. Botet Escriba a =E9crit : >> Le 24/05/13 19:07, Vicente J. Botet Escriba a =E9crit : >>> Hi, >>> >>> What is the rationale for when_all to return >>> future>> instead of future>? >>> What is the rationale for when_any to return >>> future>> instead of future> ? >>> >>> >> I have one more question about when_any. What would be the expected >> behavior when when_any has parameters that shared the same shared >> state, as in >> >> std::shared_future fi1 =3D >> std::async(calculate_the_answer_to_life_the_universe_and_everything).sha= re(); >> std::shared_future fi2 =3D fi1; >> std::when_any(fi1, fi2).wait(); >> This will wait until the async finishes. Both futures become ready together, so there is no problem here. > Or even this radical one >=20 > std::future fi1 =3D > std::async(calculate_the_answer_to_life_the_universe_and_everything).shar= e(); > std::when_any(fi1, fi1).wait(); This shouldn't compile, since fi1 is not copyable, so you should have to move it into the when_any call. Under the current spec, the interface allows it to compile, but it may fail due to internal implementation details, in which case the spec needs updating. If it did compile then I would expect it to complain about an invalid future, since after moving the first arg the second one will be empty. Anthony --=20 Author of C++ Concurrency in Action http://www.stdthread.co.uk/book/ just::thread C++11 thread library http://www.stdthread.co.uk Just Software Solutions Ltd http://www.justsoftwaresolutions.co.uk 15 Carrallack Mews, St Just, Cornwall, TR19 7UL, UK. Company No. 5478976 --=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/?hl=3Den. .