From -7238669899776357496 X-Google-Thread: 7894ca11fe,8390690191732735 X-Google-Attributes: gid7894ca11fe,public,usenet X-Google-NewGroupId: yes X-Google-Language: ENGLISH,ASCII-7-bit Path: g2news1.google.com!news1.google.com!news.glorb.com!news.alt.net!frodo.cs.rpi.edu!not-for-mail From: Scott Meyers Newsgroups: comp.std.c++ Subject: Re: Why is std::array an aggregate? Date: Sat, 19 Dec 2009 21:37:48 CST Organization: albasani.net Lines: 31 Sender: cppmods@cs.rpi.edu Approved: stephen.clamage@sun.com Message-ID: References: <2fba9f88-3e5e-472f-a2fa-b7b415f07f69@g26g2000yqe.googlegroups.com> NNTP-Posting-Host: netlab.cs.rpi.edu Content-Type: text/plain; charset=ISO-8859-1; format=flowed To: (Usenet) Return-Path: X-Original-Date: Sat, 19 Dec 2009 08:31:41 -0800 X-Submission-Address: std-c++@netlab.cs.rpi.edu Xref: g2news1.google.com comp.std.c++:1943 James Kanze wrote: > Presumably, so that it can be statically initialized, in order > to avoid order of initialization problems. (It still needs a > mechanism for the number of elements to be determined, > statically, from the initialization list, in order to be truly > useful.) Well, the size of the std::array is part of its type, so if dynamic initialization were permitted, all we'd need would be a specification for what happens if the number of clauses in the init list didn't match the declared size of the std::array. To keep things semi-consistent with aggregate initialization, we could say that std::array elements without initializers would be value initialized, and if too many initializers were specified, an exception would be thrown. Actually, now that I think of it, I'm pretty sure std::array objects can be dynamically initialized: std::array a { f(), g(), h() }; // legal, no? As for avoiding order of initialization problems, why should std::array be special in this regard? Scott -- [ comp.std.c++ is moderated. To submit articles, try just posting with ] [ your news-reader. If that fails, use mailto:std-c++@netlab.cs.rpi.edu] [ --- Please see the FAQ before posting. --- ] [ FAQ: http://www.comeaucomputing.com/csc/faq.html ]