220 35826 article Path: news.gmane.org!.POSTED!not-for-mail From: =?UTF-8?Q?Jonathan_M=c3=bcller?= Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Output parameters Date: Sat, 9 Dec 2017 20:50:01 +0100 Lines: 41 Approved: news@gmane.org Message-ID: References: <1c1bb50b-2d59-4247-a158-158065fb1a9a@isocpp.org> 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 1512849005 18127 195.159.176.226 (9 Dec 2017 19:50:05 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Sat, 9 Dec 2017 19:50:05 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.5.0 To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBCUMHC4Z6QGBB3H4WDIQKGQE3BG3NNY@isocpp.org Sat Dec 09 20:50:01 2017 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-wr0-f198.google.com ([209.85.128.198]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1eNl8I-0004S5-M2 for gclcip-std-proposals@m.gmane.org; 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[91.2.133.29]) by smtp.gmail.com with ESMTPSA id b66sm4545712wmh.32.2017.12.09.11.50.02 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 09 Dec 2017 11:50:02 -0800 (PST) In-Reply-To: <1c1bb50b-2d59-4247-a158-158065fb1a9a@isocpp.org> Content-Language: en-US X-Original-Sender: jonathanmueller.dev@gmail.com X-Original-Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=JwqQIfVR; spf=pass (google.com: domain of jonathanmueller.dev@gmail.com designates 209.85.220.41 as permitted sender) smtp.mailfrom=jonathanmueller.dev@gmail.com; dmarc=pass (p=NONE sp=NONE 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:35826 Archived-At: On 09.12.2017 20:22, odomobo@gmail.com wrote: > It would be useful for c++ to have an idiomatic way to express strictly= =20 > output parameters. This would especially be useful for self-documenting= =20 > APIs, and would help prevent usage errors with 0 runtime cost. >=20 > It should be easy to implement using templates. Something like the=20 > following: >=20 > | > voidfoo(out_refo){o =3D10;} >=20 > voidmain() > { > intx; > =C2=A0 =C2=A0 foo(x); > =C2=A0 =C2=A0 cout < } > | >=20 > I've attached my (probably buggy) proof-of-concept. >=20 > I'm curious why the stl doesn't already have something like this. Was it= =20 > overlooked, or is there a good reason against having this? >=20 I covered that topic in depth in this blog post:=20 http://foonathan.net/blog/2016/10/26/output-parameter.html --=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/eae7f2ca-01dc-9683-0262-af99abdf7e35%40gmail.com= .. .