220 33821 <8213093.ESMYL9sCCc@tjmaciei-mobl1> article Path: news.gmane.org!.POSTED!not-for-mail From: Thiago Macieira Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Re: string_view for fstream::open() Date: Fri, 11 Aug 2017 09:34:23 -0700 Lines: 29 Approved: news@gmane.org Message-ID: <8213093.ESMYL9sCCc@tjmaciei-mobl1> References: Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" X-Trace: blaine.gmane.org 1502469280 25070 195.159.176.226 (11 Aug 2017 16:34:40 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Fri, 11 Aug 2017 16:34:40 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBCB4TK757YBRBGFZW7GAKGQELTTTJHI@isocpp.org Fri Aug 11 18:34:34 2017 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-pf0-f200.google.com ([209.85.192.200]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1dgCtI-0005qB-Ap for gclcip-std-proposals@m.gmane.org; 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mx.google.com; spf=pass (google.com: domain of thiago@macieira.org designates 78.47.120.188 as permitted sender) smtp.mailfrom=thiago@macieira.org Original-Received: from gondolin.macieira.info (gondolin.macieira.info. [78.47.120.188]) by mx.google.com with ESMTP id i19si1253064iod.30.2017.08.11.09.34.32 for ; Fri, 11 Aug 2017 09:34:32 -0700 (PDT) Received-SPF: pass (google.com: domain of thiago@macieira.org designates 78.47.120.188 as permitted sender) client-ip=78.47.120.188; Original-Received: from tjmaciei-mobl1.localnet (jfdmzpr05-ext.jf.intel.com [134.134.139.74]) by gondolin.macieira.info (Postfix) with ESMTPSA id 3CD4711B6FA for ; Fri, 11 Aug 2017 09:34:31 -0700 (PDT) In-Reply-To: X-Original-Sender: thiago@macieira.org X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of thiago@macieira.org designates 78.47.120.188 as permitted sender) smtp.mailfrom=thiago@macieira.org 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:33821 Archived-At: On sexta-feira, 11 de agosto de 2017 02:16:19 PDT Olaf van der Spek wrote: > > The requirement in order to provide defined behaviour that the character > > after the view must be readable is publicly documented. > > Ouch. IMO that's not a reasonable requirement / interface. > > > Failure by the end > > user to ensure this leads to UB, specifically, a segfault. > > What could the committee do about this? Why should the committee do something about it? void *ptr = mmap(nullptr, 4096, PROT_READ, MAP_PRIVATE | MAP_ANON, -1, 0); std::string_view(static_cast(ptr), 4096); The character after the end of the string is not readable. Why do you want me to have 100% overhead? -- Thiago Macieira - thiago (AT) macieira.info - thiago (AT) kde.org Software Architect - Intel Open Source Technology Center -- 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. To view this discussion on the web visit https://groups.google.com/a/isocpp.org/d/msgid/std-proposals/8213093.ESMYL9sCCc%40tjmaciei-mobl1. .