220 28535 <590c1dd8-e59f-48d3-9e66-bb7165d1b8b3@isocpp.org> article Path: news.gmane.org!.POSTED!not-for-mail From: Greg Marr Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: A plea to reconsider adding Structured Bindings to language Date: Wed, 5 Oct 2016 07:36:07 -0700 (PDT) Lines: 129 Approved: news@gmane.org Message-ID: <590c1dd8-e59f-48d3-9e66-bb7165d1b8b3@isocpp.org> References: <201610051238.17863.marc.mutz@kdab.com> <201610051300.02280.marc.mutz@kdab.com> <201610051411.30312.marc.mutz@kdab.com> <073a7698-1388-4858-b6fa-b2b62a4fb6f1@isocpp.org> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="----=_Part_4481_1268614287.1475678167472" X-Trace: blaine.gmane.org 1475678197 26783 195.159.176.226 (5 Oct 2016 14:36:37 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Wed, 5 Oct 2016 14:36:37 +0000 (UTC) To: ISO C++ Standard - Future Proposals Original-X-From: std-proposals+bncBDEZH3XFPIINRH6UX4CRUBEWK5L7K@isocpp.org Wed Oct 05 16:36:28 2016 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-ua0-f197.google.com ([209.85.217.197]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1brnIq-00042a-3l for gclcip-std-proposals@m.gmane.org; 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Wed, 05 Oct 2016 07:36:13 -0700 (PDT) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.107.27.213 with SMTP id b204ls383077iob.41.gmail; Wed, 05 Oct 2016 07:36:08 -0700 (PDT) X-Received: by 10.36.137.67 with SMTP id s64mr1529819itd.1.1475678168199; Wed, 05 Oct 2016 07:36:08 -0700 (PDT) In-Reply-To: X-Original-Sender: gregmmarr@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:28535 Archived-At: ------=_Part_4481_1268614287.1475678167472 Content-Type: multipart/alternative; boundary="----=_Part_4482_242691810.1475678167472" ------=_Part_4482_242691810.1475678167472 Content-Type: text/plain; charset=UTF-8 On Wednesday, October 5, 2016 at 10:26:09 AM UTC-4, Ville Voutilainen wrote: > > On 5 October 2016 at 17:20, Greg Marr > > wrote: > >> > Only if you say that you want references, using "auto &" or "auto > &&". > >> > If > >> > you use "auto", you just get copies. > >> > >> You get a copy of the whole struct, not copies of individual bindings. > > > > > > That's not what's described in the paper. Has it changed since > > That's what the wording of the facility does, and what the clang > implementation does. > > > https://isocpp.org/files/papers/p0217r0.html ? > > See http://open-std.org/JTC1/SC22/WG21/docs/papers/2016/p0217r1.html > Thanks. The relevant parts of that paper that significantly change this feature from the one I referenced before: That paper incorporates feedback from the EWG session in Jacksonville as follows: - introduced variables are, in all cases, references to the value of the initializer - the cv-qualifiers and ref-qualifier of the decomposition declaration are applied to the reference introduced for the initializer, not for the individual member aliases -- 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/590c1dd8-e59f-48d3-9e66-bb7165d1b8b3%40isocpp.org. ------=_Part_4482_242691810.1475678167472 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
On Wednesday, October 5, 2016 at 10:26:09 AM UTC-4, Ville = Voutilainen wrote:
On 5 October= 2016 at 17:20, Greg Marr <greg...@gmail.com> wrote:
>> > Only if you say that you want references, using "aut= o &" or "auto &&".
>> > If
>> > you use "auto", you just get copies.
>>
>> You get a copy of the whole struct, not copies of individual b= indings.
>
>
> That's not what's described in the paper. =C2=A0Has it cha= nged since

That's what the wording of the facility does, and what the clang
implementation does.

> https://is= ocpp.org/files/papers/p0217r0.html ?

See http://open-= std.org/JTC1/SC22/WG21/docs/papers/2016/p0217r1.html

Thanks. =C2=A0The relevant parts of th= at paper that significantly change this feature from the one I referenced b= efore:
=C2=A0
That paper incorporates feedback from the EWG= session in Jacksonville as follows:
      • introduced variables are, in all cases, references to the val= ue of the initializer
      • the cv-qualifiers and ref-qualifier of the de= composition declaration are applied to the reference introduced for the ini= tializer, not for the individual member aliases

    --
    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/590c1dd8-e59f-48d3-9e66-bb7165d1b8b3= %40isocpp.org.
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