220 41121 <20181129060523.GA21632@noemi.bahnhof.se> article Path: news.gmane.org!.POSTED!not-for-mail From: Magnus Fromreide Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Function Parameter of Struct Type -> Named Parameters Date: Thu, 29 Nov 2018 07:05:23 +0100 Lines: 39 Approved: news@gmane.org Message-ID: <20181129060523.GA21632@noemi.bahnhof.se> References: Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" X-Trace: blaine.gmane.org 1543471403 28166 195.159.176.226 (29 Nov 2018 06:03:23 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Thu, 29 Nov 2018 06:03:23 +0000 (UTC) User-Agent: Mutt/1.10.1 (2018-07-13) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBDELLREETMBRBJ4D73PQKGQE75MFDQA@isocpp.org Thu Nov 29 07:03:19 2018 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-yw1-f69.google.com ([209.85.161.69]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1gSFPz-0007DZ-7k for gclcip-std-proposals@m.gmane.org; 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[130.236.254.3]) by mx.google.com with ESMTPS id u130si578520ywa.406.2018.11.28.22.05.27 for (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 28 Nov 2018 22:05:27 -0800 (PST) Received-SPF: pass (google.com: domain of magfr@lysator.liu.se designates 130.236.254.3 as permitted sender) client-ip=130.236.254.3; Original-Received: from mail.lysator.liu.se (localhost [127.0.0.1]) by mail.lysator.liu.se (Postfix) with ESMTP id EA2964000B for ; Thu, 29 Nov 2018 07:05:24 +0100 (CET) Original-Received: from noemi.bahnhof.se (h-155-4-131-135.NA.cust.bahnhof.se [155.4.131.135]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.lysator.liu.se (Postfix) with ESMTPSA id C087C40007 for ; Thu, 29 Nov 2018 07:05:24 +0100 (CET) Mail-Followup-To: std-proposals@isocpp.org Content-Disposition: inline In-Reply-To: X-Virus-Scanned: ClamAV using ClamSMTP X-Original-Sender: magfr@lysator.liu.se X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of magfr@lysator.liu.se designates 130.236.254.3 as permitted sender) smtp.mailfrom=magfr@lysator.liu.se; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=liu.se Precedence: list Mailing-list: list std-proposals@isocpp.org; contact std-proposals+owners@isocpp.org List-ID: X-Spam-Checked-In-Group: std-proposals@isocpp.org 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:41121 Archived-At: On Thu, Nov 29, 2018 at 02:57:55PM +1000, Andrew Tomazos wrote: > It seems to me that a function that takes a struct combined with C++20 > designated initializers gets us very close to named parameters: > > struct FooParameters { > int bar; > float baz; > }; > float foo(FooParameters params) { > return (params.bar + 3) * params.baz; > } > int main() { > foo({bar: 4, baz: 3.2}); > } > > If we added some syntactic sugar that... > 1. Removed the need to give the parameter struct type a name > 2. Introduced the parameter struct members into the function definition > scope. I think this misses a lot of benefits and would propose two other rules: 1. Allow anonymous structs Similar to anonymous unions. This is already done by VC++ and as an extension by g++ and clang++. 2. Implicitly assume that a call to a function wants to call a function named thus and see if some overload could fit the provieded tokens, this would allow void fun(enum { something, other } x); to do the right thing as well. /MF -- 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/20181129060523.GA21632%40noemi.bahnhof.se. .