220 41481 <1e6e2f7e-cc29-7f39-f421-3674cd71ce14@gmail.com> article Path: news.gmane.org!.POSTED.blaine.gmane.org!not-for-mail From: Matthew Woehlke Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Allow array as function return value Date: Wed, 20 Feb 2019 14:33:38 -0500 Approved: news@gmane.org Message-ID: <1e6e2f7e-cc29-7f39-f421-3674cd71ce14@gmail.com> References: <8a165c32-718a-4247-93b4-44235a2cf122@isocpp.org> <65d69c2c-3fa1-40a5-8120-53bfd345ac90@isocpp.org> <7eac0e9f-4042-45d6-93b3-de89ba4ebae0@isocpp.org> Reply-To: std-proposals@isocpp.org Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Injection-Info: blaine.gmane.org; posting-host="blaine.gmane.org:195.159.176.226"; logging-data="32073"; mail-complaints-to="usenet@blaine.gmane.org" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.4.0 To: std-proposals@isocpp.org, Nicol Bolas Original-X-From: std-proposals+bncBC37LBFWUIFBBFGXW3RQKGQETOD7G6Y@isocpp.org Wed Feb 20 20:33:43 2019 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-qk1-f198.google.com ([209.85.222.198]) by blaine.gmane.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.89) (envelope-from ) id 1gwXck-0008El-Hr for gclcip-std-proposals@m.gmane.org; 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[66.194.253.20]) by smtp.googlemail.com with ESMTPSA id f7sm12566675qkb.33.2019.02.20.11.33.38 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 20 Feb 2019 11:33:38 -0800 (PST) Openpgp: preference=signencrypt In-Reply-To: <7eac0e9f-4042-45d6-93b3-de89ba4ebae0@isocpp.org> Content-Language: en-US X-Original-Sender: mwoehlke.floss@gmail.com X-Original-Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b="NCiE7/jm"; spf=pass (google.com: domain of mwoehlke.floss@gmail.com designates 209.85.220.41 as permitted sender) smtp.mailfrom=mwoehlke.floss@gmail.com; dmarc=pass (p=NONE sp=QUARANTINE 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:41481 Archived-At: On 19/02/2019 22.55, Nicol Bolas wrote: > From a more objective POV, my feeling is that `std::array` really only has > two significant flaws relative to to C arrays: not being able to omit the > size of an array while still specifying the type (which is a matter of > CTAD), and the general verbosity of multi-dimensional arrays. Well, I can help with the second... shortest ever proposal? namespace std { template struct array : array, First> {}; } Example: std::array x; x[1][1][1] = 42; Implementing operator() to do multi-level indexing is left as an exercise for the reader. Of course, the reason we don't have this yet is because folks want to argue about packing order and whatnot. It turns out multi-dimensional arrays aren't actually as simple as you'd think. -- Matthew -- 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/1e6e2f7e-cc29-7f39-f421-3674cd71ce14%40gmail.com. .