220 2925 article Path: news.gmane.org!not-for-mail From: Tony V E Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: std::optional -- request for feedback on the wording Date: Sun, 17 Feb 2013 13:34:50 -0500 Lines: 34 Approved: news@gmane.org Message-ID: References: <511FFA5B.7050204@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 X-Trace: ger.gmane.org 1361126096 14487 80.91.229.3 (17 Feb 2013 18:34:56 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sun, 17 Feb 2013 18:34:56 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBCUZ5QWKNQIMVRMERECRUBALTGIAU@isocpp.org Sun Feb 17 19:35:11 2013 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-we0-f198.google.com ([74.125.82.198]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1U794x-00076M-Fb for gclcip-std-proposals@m.gmane.org; Sun, 17 Feb 2013 19:35:11 +0100 Original-Received: by mail-we0-f198.google.com with SMTP id k14sf5877898wer.5 for ; Sun, 17 Feb 2013 10:34:51 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=x-received:x-beenthere:x-received:x-received:received-spf :mime-version:x-received: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; bh=NAgmF+yApiKnCZ0Zq8v+HJcU8dMZvkt25HeVYWT+DA0=; b=J7Ay3mHiJCOTRNiVpLRY3h4qDc+XIM/XfYgijt6try4iK+6WVat02OVx8pjGS9Hy6z Xuexsg9ILmkLacj5NP6OjlU//44M3e0Yo9ZI+gt84Mz074OFO+PaD3+3XjYTwYiMO2o6 lIaYbRJbap5SMvVy9jmhJhM73Tn8nCDA7NqqnP7qh3pghs/j1sm0WOgcNAZhTtj9C8De DmtW1ov+G+sSEqM26PeNkydc5psGOX5cVrD8vbX81VPFWTuiCGB8+GcRSxz55wx84GaR 4BV1UTPPSNo7IU1RKf71VoxHH80vBRiPMHVMiyMiETxNUNNHN X-Received: by 10.112.50.46 with SMTP id z14mr41192lbn.12.1361126091124; Sun, 17 Feb 2013 10:34:51 -0800 (PST) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.152.104.136 with SMTP id ge8ls125682lab.107.gmail; Sun, 17 Feb 2013 10:34:50 -0800 (PST) X-Received: by 10.112.29.72 with SMTP id i8mr4714136lbh.33.1361126090501; Sun, 17 Feb 2013 10:34:50 -0800 (PST) X-Received: by 10.112.29.72 with SMTP id i8mr4714135lbh.33.1361126090478; Sun, 17 Feb 2013 10:34:50 -0800 (PST) Original-Received: from mail-la0-x22c.google.com ([2a00:1450:4010:c03::22c]) by mx.google.com with ESMTPS id iz6si9184779lab.128.2013.02.17.10.34.50 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Sun, 17 Feb 2013 10:34:50 -0800 (PST) Received-SPF: pass (google.com: domain of tvaneerd@gmail.com designates 2a00:1450:4010:c03::22c as permitted sender) client-ip=2a00:1450:4010:c03::22c; Original-Received: by mail-la0-f44.google.com with SMTP id eb20so4898786lab.17 for ; Sun, 17 Feb 2013 10:34:50 -0800 (PST) X-Received: by 10.152.48.45 with SMTP id i13mr8299609lan.11.1361126090265; Sun, 17 Feb 2013 10:34:50 -0800 (PST) Original-Received: by 10.112.14.75 with HTTP; Sun, 17 Feb 2013 10:34:50 -0800 (PST) In-Reply-To: <511FFA5B.7050204@wanadoo.fr> X-Original-Sender: tvaneerd@gmail.com X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of tvaneerd@gmail.com designates 2a00:1450:4010:c03::22c as permitted sender) smtp.mail=tvaneerd@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:2925 Archived-At: On Sat, Feb 16, 2013 at 4:30 PM, Vicente J. Botet Escriba wrote: > > > * optional::optional(const optional& rhs); > > What about adding a post-condition on the copied value > false == bool(rhs) || rhs.value() == this->value() > You can't guarantee rhs.value() == this->value() for all T. You are probably assuming T is Regular. > > What about adding a post-condition on the copied value > v == this->value() > Same here. Tony -- --- 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/?hl=en. .