220 34297 <603cdb5a-4da5-5f75-55ec-6292bd4ef229@technion.ac.il> article Path: news.gmane.org!.POSTED!not-for-mail From: Eyal Rozenberg Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Re: Idea: Extension of structured bindings to definition of structs Date: Tue, 5 Sep 2017 00:00:35 +0200 Lines: 55 Approved: news@gmane.org Message-ID: <603cdb5a-4da5-5f75-55ec-6292bd4ef229@technion.ac.il> References: <59dcbbbc-c536-4b7b-9c88-0638fb0cd58a@technion.ac.il> <7b9bf263-d3ca-42bf-aed6-4c7606782a28@isocpp.org> <1762295.OciJaA9sdk@tjmaciei-mobl1> <74349bfe-bb5a-a2ce-4142-5d46103d1d9f@technion.ac.il> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: quoted-printable X-Trace: blaine.gmane.org 1504562460 14577 195.159.176.226 (4 Sep 2017 22:01:00 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Mon, 4 Sep 2017 22:01:00 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; 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[192.16.191.27]) by mx.google.com with ESMTPS id z55si8586241edb.21.2017.09.04.15.00.48 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 04 Sep 2017 15:00:48 -0700 (PDT) Received-SPF: pass (google.com: domain of srs0=5sp6a=af=technion.ac.il=eyalroz@cwi.nl designates 192.16.191.27 as permitted sender) client-ip=192.16.191.27; Original-Received: from fester.cwi.nl (fester.cwi.nl [192.16.191.27]) by fester.cwi.nl (8.14.4/8.12.3) with ESMTP id v84M0gBd032432; Tue, 5 Sep 2017 00:00:42 +0200 Original-Received: from [192.168.2.1] (ip565d4370.direct-adsl.nl [86.93.67.112] (may be forged)) (authenticated bits=0) by fester.cwi.nl (8.14.4/8.12.3) with ESMTP id v84M0emG032430 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NO); Tue, 5 Sep 2017 00:00:41 +0200 In-Reply-To: Content-Language: en-US X-Original-Sender: eyalroz@technion.ac.il X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of srs0=5sp6a=af=technion.ac.il=eyalroz@cwi.nl designates 192.16.191.27 as permitted sender) smtp.mailfrom=SRS0=5SP6A=AF=technion.ac.il=eyalroz@cwi.nl 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:34297 Archived-At: Please read my answer to Nicol Bolas. To reiterate briefly: I don't want to do any of those things. I would use this struct's=20 members, and they're in a struct to indicate that they're related and to=20 name them together. More importantly, I would have the person reading my code go "Oh, so=20 he's using parts of the car" rather than have to to keep track of the=20 relation of the loose variables in his/her mind. (This especially true if my function was named scavage_junkyard() rather=20 than get_car_parts() ). Eyal On 9/4/17 9:04 PM, Nevin Liber wrote: > On Mon, Sep 4, 2017 at 9:16 AM, Eyal Rozenberg > wrote: >=20 > I'm not actually suggesting a new way to create a type. The type is > created anyway if I write: >=20 > =C2=A0 struct { > =C2=A0 =C2=A0 =C2=A0 decltype(std::get<0>(get_car_parts())) engine; > =C2=A0 =C2=A0 =C2=A0 decltype(std::get<0>(get_car_parts())) dashboar= d; > =C2=A0 =C2=A0 =C2=A0 decltype(std::get<0>(get_car_parts())) stickshi= ft; > =C2=A0 } car_parts =3D get_car_parts(); >=20 >=20 > Syntactic sugar or not, what can you do with an object of that type? =20 > You can either: >=20 > * Pass it to a templated function > * Capture it in a lambda >=20 > As I stated before, that usage seems fairly marginal and not worth a=20 > language feature. > --=20 > =C2=A0Nevin ":-)" Liber=C2=A0 > =C2=A0+1-847-691-1404 --=20 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 e= mail 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/603cdb5a-4da5-5f75-55ec-6292bd4ef229%40technion.= ac.il. .