220 41474 article Path: news.gmane.org!.POSTED.blaine.gmane.org!not-for-mail From: Jake Arkinstall Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Allow array as function return value Date: Tue, 19 Feb 2019 16:30:33 +0000 Approved: news@gmane.org Message-ID: References: <8a165c32-718a-4247-93b4-44235a2cf122@isocpp.org> <65d69c2c-3fa1-40a5-8120-53bfd345ac90@isocpp.org> Reply-To: std-proposals@isocpp.org Mime-Version: 1.0 Content-Type: multipart/alternative; boundary="0000000000004e8728058241c312" Injection-Info: blaine.gmane.org; posting-host="blaine.gmane.org:195.159.176.226"; logging-data="244259"; mail-complaints-to="usenet@blaine.gmane.org" To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBDCZX3WUUQFRBNO6WDRQKGQEGHWTY7Y@isocpp.org Tue Feb 19 17:30:49 2019 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-it1-f197.google.com ([209.85.166.197]) by blaine.gmane.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.89) (envelope-from ) id 1gw8IC-0011O5-A8 for gclcip-std-proposals@m.gmane.org; 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[209.85.220.41]) by mx.google.com with SMTPS id d188sor4235179ite.10.2019.02.19.08.30.45 for (Google Transport Security); Tue, 19 Feb 2019 08:30:45 -0800 (PST) Received-SPF: pass (google.com: domain of jake.arkinstall@gmail.com designates 209.85.220.41 as permitted sender) client-ip=209.85.220.41; X-Received: by 2002:a24:4706:: with SMTP id t6mr2432063itb.109.1550593844740; Tue, 19 Feb 2019 08:30:44 -0800 (PST) In-Reply-To: <65d69c2c-3fa1-40a5-8120-53bfd345ac90@isocpp.org> X-Original-Sender: jake.arkinstall@gmail.com X-Original-Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=kGSgFaeU; spf=pass (google.com: domain of jake.arkinstall@gmail.com designates 209.85.220.41 as permitted sender) smtp.mailfrom=jake.arkinstall@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:41474 Archived-At: --0000000000004e8728058241c312 Content-Type: text/plain; charset="UTF-8" On Tue, 19 Feb 2019, 15:52 will wray (Trying one more time - previous attempts went to the google groups spam > filter) > > C-array is an atomic aggregate - a pure crystal condensate of one atom > type. > > This thread is to discuss improved language support for C-array via array > return. > > (It is not about addressing std::array shortcomings. > It is not an either / or. > C-array and std::array are different tools for different tasks.) > >> The fact that array return is now technically feasible shows how far C++ > language > specification has risen above its C roots. > What was impossible for forty years is now possible. > >> Raw array is analogous to raw pointer. > We've outgrown the urge to wrap all pointers - that's not so smart. > Raw pointers have been rehabilitated as the right tool for low level code. > Raw arrays deserve to be rehabilitated, with a little language level love. > I'm not so sure on that. std::array gives the compiler the knowledge of the size so that the user doesn't have to pass it around manually, but in a compiled executable I don't see any difference except for removal of jump instructions in the std::array case thanks to loop unrolling. Im definitely against any notion of removing raw arrays from the language (because it is nonsensical), but I also never use them explicitly unless I'm doing unmentionable casty and c-stringy things in low latency settings - and even then I'm doing it via std::array.data(). > On Monday, February 18, 2019 at 11:33:19 AM UTC-5, Joel Falcou wrote: >> >> C style arrays must disappear as they have no value over std::array >> > > (Eh? Trollish joke?) > C-array is essential to implement std::array - it can't and won't > disappear. > > std::array is a molecular aggregate, an abstract compound > >> 'compound': make (something bad) worse; intensify the negative aspects >> of. > > -- 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/CAC%2B0CCPKvKDGrYdvLwPGtKYQ-2%3DmOFdi5tAA0PzwU_JAvQHjtQ%40mail.gmail.com. --0000000000004e8728058241c312 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
On Tue, = 19 Feb 2019, 15:52 will wray <wjwray= @gmail.com wrote:
(Trying one more time - previous attempts went to the google groups spa= m filter)

C-array is an atomic ag= gregate - a pure crystal condensate of one atom type.

This thread is to discuss= improved language support for C-array via array return.
<= span style=3D"font-family:Roboto,"Helvetica Neue",Helvetica,Arial= ,sans-serif;font-size:small">
(It is not about addressing std::array shortcomings.
=C2=A0It is not an either / or.=C2=A0=
=C2=A0C-array and std::array are different tools for different t= asks.)
The= fact that array return is now technically feasible shows how far C++ langu= age
specification has risen above its C roots.
What was impossible for forty years is now possible.
Raw array is analogous to ra= w pointer.
We've outgrown the urge to wrap all pointers - that's= not so smart.
Raw pointers have been rehabilitated as the right tool fo= r low level code.
Raw arrays deserve to be rehabilitated, with a little = language level love.
=

I'm not so su= re on that. std::array gives the compiler the knowledge of the size so that= the user doesn't have to pass it around manually, but in a compiled ex= ecutable I don't see any difference except for removal of jump instruct= ions in the std::array case thanks to loop unrolling.

Im definitely against any notion of removing = raw arrays from the language (because it is nonsensical), but I also never = use them explicitly unless I'm doing unmentionable casty and c-stringy = things in low latency settings - and even then I'm doing it via std::ar= ray.data().

=

On= Monday, February 18, 2019 at 11:33:19 AM UTC-5, Joel Falcou wrote:<= blockquote class=3D"gmail_quote" style=3D"font-family:Roboto,"Helvetic= a Neue",Helvetica,Arial,sans-serif;font-size:small;margin:0px 0px 0px = 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">C style arra= ys must disappear as they have no value over std::array=C2=A0

(Eh?= Trollish joke?)
C-array is essential to = implement std::array - it can't and won't disappear.

std::array is a = molecular aggregate, an abstract compound
= 'compound':=C2=A0make (something bad) wors= e; intensify the negative aspects of.
=

--
You received this message because you are subscribed to the Google Groups &= quot;ISO C++ Standard - Future Proposals" group.
To unsubscribe from this group and stop receiving emails from it, send an e= mail to std-proposa= ls+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/CAC%2B0CCPKvK= DGrYdvLwPGtKYQ-2%3DmOFdi5tAA0PzwU_JAvQHjtQ%40mail.gmail.com.
--0000000000004e8728058241c312-- .