220 33828 article Path: news.gmane.org!.POSTED!not-for-mail From: Olaf van der Spek Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Re: string_view for fstream::open() Date: Fri, 11 Aug 2017 19:26:33 +0200 Lines: 34 Approved: news@gmane.org Message-ID: References: <8213093.ESMYL9sCCc@tjmaciei-mobl1> 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 1502472397 2161 195.159.176.226 (11 Aug 2017 17:26:37 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Fri, 11 Aug 2017 17:26:37 +0000 (UTC) To: "ISO C++ Standard - Future Proposals" Original-X-From: std-proposals+bncBC5NB45SSABBBSWRW7GAKGQE6R4MPPY@isocpp.org Fri Aug 11 19:26:30 2017 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-it0-f72.google.com ([209.85.214.72]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1dgDhe-00009K-5Y for gclcip-std-proposals@m.gmane.org; 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[2607:f8b0:400d:c0d::232]) by mx.google.com with ESMTPS id 28si1206068qtn.542.2017.08.11.10.26.34 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 11 Aug 2017 10:26:34 -0700 (PDT) Received-SPF: pass (google.com: domain of olafvdspek@gmail.com designates 2607:f8b0:400d:c0d::232 as permitted sender) client-ip=2607:f8b0:400d:c0d::232; Original-Received: by mail-qt0-x232.google.com with SMTP id a18so24888309qta.0 for ; Fri, 11 Aug 2017 10:26:34 -0700 (PDT) X-Received: by 10.200.46.7 with SMTP id r7mr24698580qta.42.1502472394359; Fri, 11 Aug 2017 10:26:34 -0700 (PDT) Original-Received: by 10.12.174.87 with HTTP; Fri, 11 Aug 2017 10:26:33 -0700 (PDT) In-Reply-To: <8213093.ESMYL9sCCc@tjmaciei-mobl1> X-Original-Sender: olafvdspek@gmail.com X-Original-Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=B1zQGcXP; spf=pass (google.com: domain of olafvdspek@gmail.com designates 2607:f8b0:400d:c0d::232 as permitted sender) smtp.mailfrom=olafvdspek@gmail.com; dmarc=pass (p=NONE sp=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:33828 Archived-At: 2017-08-11 18:34 GMT+02:00 Thiago Macieira : > 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? I don't know.. Niall suggested the committee could do something about it so I'm wondering what it is they could do. > 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? I don't -- Olaf -- 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. 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