220 8763 article Path: news.gmane.org!not-for-mail From: Sebastian Gesemann Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Re: Comments on 2d api for c++ N3888.pdf Date: Thu, 23 Jan 2014 12:09:41 +0100 Lines: 37 Approved: news@gmane.org Message-ID: References: <9105f9b2-e15d-4bf8-a4a1-65ebc3657eb0@isocpp.org> <905c4911-c4d0-4356-bdd1-eeee0d232cf6@isocpp.org> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-Trace: ger.gmane.org 1390475376 3298 80.91.229.3 (23 Jan 2014 11:09:36 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Thu, 23 Jan 2014 11:09:36 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBDO4ZQHJWIBRB5XQQOLQKGQE57QTKPQ@isocpp.org Thu Jan 23 12:09:45 2014 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-qa0-f69.google.com ([209.85.216.69]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1W6IAJ-0001BM-BW for gclcip-std-proposals@m.gmane.org; Thu, 23 Jan 2014 12:09:43 +0100 Original-Received: by mail-qa0-f69.google.com with SMTP id w8sf2636862qac.0 for ; Thu, 23 Jan 2014 03:09:42 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:x-original-sender :x-original-authentication-results:reply-to:precedence:mailing-list :list-id:list-post:list-help:list-archive:list-subscribe :list-unsubscribe:content-type; bh=I2eUR+Utk8c+7h3Hh48qpvnvzgqMZwsNMgK++5k4Hkg=; b=ZR8CME33vAnBeXXGGnkN2lhmgnXgtS6sJEiis4ahut3peu6moZGQ2o294HvaFSSiAy /brtj8xbn3b5ChM5opRhF6bHet9R8Xsmr2IWfDw7jgXrlRdAGUc+S200BlphY5kJZbkL n0d/i3mCFrNZkeONoi6zmhyznIXsIJml63AR0G0RroBZHdiRj6JHe3ryerw3p+kEFQCj SpDlBdN3ZY7xlMYpmldtAu+9Z8U6694DNKcDB06upKnsz9GXTi+zAyGd0aSSaaswbpoY pRDbPdSPRRbhoscqfuTHidCad7Zoq7ZxDoE5Q/X9/yUsBIfMhzpY7Y8GbjWDmeJ2zVYy UjPQ== X-Gm-Message-State: ALoCoQnQSENqb3LyrP+eamjeP5O3MrIFNWwUNXXDLIBfuqIXoEoSd3VLPQ7hlrWXnj5w0lrahIZb X-Received: by 10.58.253.33 with SMTP id zx1mr2685206vec.10.1390475382507; Thu, 23 Jan 2014 03:09:42 -0800 (PST) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.140.87.134 with SMTP id r6ls290098qgd.47.gmail; Thu, 23 Jan 2014 03:09:42 -0800 (PST) X-Received: by 10.236.91.101 with SMTP id g65mr7025753yhf.35.1390475382054; Thu, 23 Jan 2014 03:09:42 -0800 (PST) Original-Received: from mail-qa0-x22c.google.com (mail-qa0-x22c.google.com [2607:f8b0:400d:c00::22c]) by mx.google.com with ESMTPS id f25si14892631yho.253.2014.01.23.03.09.41 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Thu, 23 Jan 2014 03:09:42 -0800 (PST) Received-SPF: pass (google.com: domain of s.gesemann@gmail.com designates 2607:f8b0:400d:c00::22c as permitted sender) client-ip=2607:f8b0:400d:c00::22c; Original-Received: by mail-qa0-f44.google.com with SMTP id w5so2003839qac.3 for ; Thu, 23 Jan 2014 03:09:41 -0800 (PST) X-Received: by 10.140.94.214 with SMTP id g80mr9862193qge.19.1390475381771; Thu, 23 Jan 2014 03:09:41 -0800 (PST) Original-Received: by 10.96.15.231 with HTTP; Thu, 23 Jan 2014 03:09:41 -0800 (PST) In-Reply-To: <905c4911-c4d0-4356-bdd1-eeee0d232cf6@isocpp.org> X-Original-Sender: s.gesemann@gmail.com X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of s.gesemann@gmail.com designates 2607:f8b0:400d:c00::22c as permitted sender) smtp.mail=s.gesemann@gmail.com; dkim=pass header.i=@gmail.com; dmarc=pass (p=NONE 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:8763 Archived-At: On Thu, Jan 23, 2014 at 11:44 AM, Edward Catmur wrote: > On Wednesday, 22 January 2014 03:01:02 UTC, germa...@gmail.com wrote: >> >> I have been taking a look at http://isocpp.org/files/papers/N3888.pdf >> The current proposal proposes this: >> >> auto x1 = some_object(); >> //Silently aliases x1 >> auto x2 = x1; >> >> I think this approach won't be satisfactory, since it violates the usual >> semantics for c++ objects, at least in the standard library. Well, there is std::shared_ptr. > I agree; the paper proposes an alternative reference semantics using the > existing unique_ptr and shared_ptr. This would allow: > > unique_ptr surf = make_surface(...); > unique_ptr ctx = make_context(*surf, ...); > > Alternatively, make_surface() could be written surface::make() etc. The copy > constructors and assignment operators would be deleted; constructors would > be private. The deleter type of a unique_ptr is not type-erased. This could be a problem especially if other kinds of resources are involved (like GPU resources). -- --- 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. Visit this group at http://groups.google.com/a/isocpp.org/group/std-proposals/. .