220 26907 <1cd5895f-df27-9cda-73cf-cbc2f1488a2c@f2.dion.ne.jp> article Path: news.gmane.org!not-for-mail From: Kazutoshi Satoda Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Better name for std::launder() ? 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[106.187.230.53]) by mx.google.com with ESMTP id d81si5127592pfb.192.2016.07.13.11.25.06 for ; Wed, 13 Jul 2016 11:25:07 -0700 (PDT) Received-SPF: pass (google.com: domain of k_satoda@f2.dion.ne.jp designates 106.187.230.53 as permitted sender) client-ip=106.187.230.53; Original-Received: from amlmta046.auone-net.jp (amlmta046-MM [10.188.23.37]) by dmta02.auone-net.jp (au one net mail) with ESMTP id 283B040007B for ; Thu, 14 Jul 2016 03:25:06 +0900 (JST) Original-Received: from [0.0.0.0] ([65.19.167.131]) by amlmta046.auone-net.jp id 5786877f0004a6a500005e820000137a4000052f8e5b; Thu, 14 Jul 2016 03:25:03 +0900 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.2.0 X-MXM-DELIVERY-TYPE: 3 X-Original-Sender: k_satoda@f2.dion.ne.jp X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of k_satoda@f2.dion.ne.jp designates 106.187.230.53 as permitted sender) smtp.mailfrom=k_satoda@f2.dion.ne.jp Precedence: list Mailing-list: list std-proposals@isocpp.org; contact std-proposals+owners@isocpp.org List-ID: X-Spam-Checked-In-Group: std-proposals@isocpp.org 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:26907 Archived-At: http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/p0137r0.html (accepted for C++17) The name std::launder() seems cryptic. There is no hint in the word "launder" to show it is about the C++ object model, lifetime, and reusing storage. The situation is likely same even if a programmer preliminarily knows about the issues it solves. Comments like "Here, compilers should suppose new object at reused storage" will be wanted each time it is used. On the other hand, assuming its rare uses, usually in libraries, a long name won't be so much problem. Thus, I think a longer and descriptive name is more appropriate. As a bonus, it will be more usable as a search key to find relevant articles about it. It could be std::suppose_new_at_reused_storage(), as a strawman. The example at [ptr.launder] would look like this: struct X { const int n; }; X *p = new X{3}; const int a = p->n; new (p) X{5}; // p does not point to new object (3.8) // because X::n is const const int b = p->n; // undefined behavior const int c = std::suppose_new_at_reused_storage(p)->n; // OK What do you think? Is it too late? Does someone know the history of the naming? -- k_satoda -- 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/1cd5895f-df27-9cda-73cf-cbc2f1488a2c%40f2.dion.ne.jp. .