220 8676 <1B534FD7-B385-4A7E-A718-3C73F0AB61DC@gmail.com> article Path: news.gmane.org!not-for-mail From: Marshall Clow Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: string_view::is_null() Date: Fri, 17 Jan 2014 20:19:07 -0800 Lines: 31 Approved: news@gmane.org Message-ID: <1B534FD7-B385-4A7E-A718-3C73F0AB61DC@gmail.com> References: <8045a4d2-721d-4725-8bb7-7a91b6f53ec8@isocpp.org> <186E0927-C962-4E34-AED0-E7509DD1F0A0@gmail.com> <7aad44d8-6b4e-438a-b309-bd898b994b34@isocpp.org> <9C2C439F-7983-4224-B272-53CAD0E2E456@gmail.com> <8E74B747-7450-41E0-8D1E-48C2D6F81535@gmail.com> <104254A6-C69A-4571-8455-89D7E466D493@gmail.com> <6a95bf9c -55c9-4ae2-966f-d1b1f4df6a37@isocpp.org> <52D9E336.1060801@knejp.de> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 (Mac OS X Mail 7.1 \(1827\)) Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable X-Trace: ger.gmane.org 1390018749 9078 80.91.229.3 (18 Jan 2014 04:19:09 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sat, 18 Jan 2014 04:19:09 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBDHIXP53REBRBQMB5CLAKGQEDDZNXZI@isocpp.org Sat Jan 18 05:19:16 2014 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-pd0-f200.google.com ([209.85.192.200]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1W4NNL-0003ky-CP for gclcip-std-proposals@m.gmane.org; Sat, 18 Jan 2014 05:19:15 +0100 Original-Received: by mail-pd0-f200.google.com with SMTP id y10sf3012312pdj.11 for ; Fri, 17 Jan 2014 20:19:14 -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:subject:from:in-reply-to:date :message-id:references: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:content-transfer-encoding; bh=xUJTf4Z5FudxLHu7hmyaqxr3sIJ8pXv7XxYlj0CjHF4=; b=a8cUJO4w8OuDyFVRv5748uJOzhUkTKxamMVKybuzkAr9RsgHRuET3E26HLLJWLs0Md SzoOauaguvU1EiY+OYLvvtg2LN1oD6XPO0UmVnMcNOawsn6pyjt625E3bRc0PfFi683B apgWhwZpZ1WwgmO4f/dGwyokXff2EyF9eJCw2yHiuuwJuEultgVTR1GOkk2FfBYGnugA K+Q4KostFHqArK9et/cH1Ln7nGI2Y5BeRx0IC79Tqkk5vo6esmjtdz086Q+9MyhlwvgU EiQVIeS/L298EvOjbQqhp7ifVEmX7Ee1XhZXSmHO6oM0UNbYGvTfHH6G906k+SLgIB1t podg== X-Gm-Message-State: ALoCoQnVam2ZdFNEkRn/vads6WjtumAn/EUdOONxOcMNdDtebuGqwEI6XkzOczRVQOSW63019l4Q X-Received: by 10.66.222.105 with SMTP id ql9mr2412862pac.9.1390018754194; Fri, 17 Jan 2014 20:19:14 -0800 (PST) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.140.91.180 with SMTP id z49ls556054qgd.59.gmail; Fri, 17 Jan 2014 20:19:13 -0800 (PST) X-Received: by 10.236.44.102 with SMTP id m66mr258901yhb.89.1390018753235; Fri, 17 Jan 2014 20:19:13 -0800 (PST) Original-Received: from mail-ob0-x236.google.com (mail-ob0-x236.google.com [2607:f8b0:4003:c01::236]) by mx.google.com with ESMTPS id s6si18020413yho.164.2014.01.17.20.19.13 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 17 Jan 2014 20:19:13 -0800 (PST) Received-SPF: pass (google.com: domain of mclow.lists@gmail.com designates 2607:f8b0:4003:c01::236 as permitted sender) client-ip=2607:f8b0:4003:c01::236; Original-Received: by mail-ob0-f182.google.com with SMTP id wn1so5300091obc.27 for ; Fri, 17 Jan 2014 20:19:12 -0800 (PST) X-Received: by 10.182.232.4 with SMTP id tk4mr4942128obc.9.1390018752776; Fri, 17 Jan 2014 20:19:12 -0800 (PST) Original-Received: from [192.168.16.50] (wsip-174-77-164-131.sd.sd.cox.net. [174.77.164.131]) by mx.google.com with ESMTPSA id h4sm19998961oel.3.2014.01.17.20.19.11 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 17 Jan 2014 20:19:11 -0800 (PST) In-Reply-To: <52D9E336.1060801@knejp.de> X-Mailer: Apple Mail (2.1827) X-Original-Sender: mclow.lists@gmail.com X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of mclow.lists@gmail.com designates 2607:f8b0:4003:c01::236 as permitted sender) smtp.mail=mclow.lists@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:8676 Archived-At: On Jan 17, 2014, at 6:13 PM, Miro Knejp wrote: >>=20 >> - both of these methods are impossible if the presumptions stated above = "begin() should never return nullptr" and "we don't need a special is_null(= )". Well, not entirely. Of course you could create some bogus object and us= e its address instead of nullptr. >>=20 > Why not set the string_view to "" in the default constructor? I believe that this is the current proposal. However, this requires creating a global variable (which some implementatio= ns will put in the code segment) for each default constructed string_view (= yes, some implementations will merge them together in the same translation = unit). =97 Marshall --=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/. .