220 29454 <110fecc1-a731-f6ad-fa8d-cfe2cb36faaa@gmail.com> article Path: news.gmane.org!.POSTED!not-for-mail From: Simon Brand Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: for...(T : t) // fold expression improvement Date: Fri, 18 Nov 2016 08:34:04 +0000 Lines: 33 Approved: news@gmane.org Message-ID: <110fecc1-a731-f6ad-fa8d-cfe2cb36faaa@gmail.com> References: <7c87350a-7ac2-489b-b107-ea25a7bd6c74@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 X-Trace: blaine.gmane.org 1479458048 6265 195.159.176.226 (18 Nov 2016 08:34:08 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Fri, 18 Nov 2016 08:34:08 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.3.0 To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBDQ5T5PGQUKRB7XZXLAQKGQEIHQ26YI@isocpp.org Fri Nov 18 09:34:04 2016 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-pf0-f199.google.com ([209.85.192.199]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1c7ecV-0000g4-I6 for gclcip-std-proposals@m.gmane.org; Fri, 18 Nov 2016 09:34:03 +0100 Original-Received: by mail-pf0-f199.google.com with SMTP id 83sf136788747pfx.1 for ; Fri, 18 Nov 2016 00:34:07 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=isocpp-org.20150623.gappssmtp.com; s=20150623; h=subject:to:references:from:message-id:date:user-agent:mime-version :in-reply-to:x-original-sender:x-original-authentication-results :reply-to:precedence:mailing-list:list-id:x-spam-checked-in-group :list-post:list-help:list-archive:list-subscribe:list-unsubscribe; bh=wsyKtdGkBcLW3biyUuPm7ojaP+S7U1iHu052oc1x0m4=; b=ubg5F+rkb1NbDfjWh7QAyfuxo9q7FzR5E67/VcBq5I0p0G8rcPXgdyLRhO9XAvkvjm hcg8kiUFlYkHqPHi6wgQHz6qP9bZZssBXzEX6iQ53WxG+IeONZMo4ky9hW+3wF2Wpimd vluGeed16ofMC7tnqH0twbqSUQtT+mgDE6ylgPc0JCJwcR1Z18/iZv02eG9ADiYqypBH jUbQAZKOVPnBX4X2y9UYzEuBhMQzfB6HXOVYpP6Sbtw4JcS4AQRsvKQYuqhMAv35oquo KWSwQsiXpb8tBJ2UjYlC3HWtAKGAEeNR2/KkVk0p+Hrs/DQGZOv/g7m/IrKMEhItfeku Utmg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to:x-original-sender :x-original-authentication-results:reply-to:precedence:mailing-list :list-id:x-spam-checked-in-group:list-post:list-help:list-archive :list-subscribe:list-unsubscribe; bh=wsyKtdGkBcLW3biyUuPm7ojaP+S7U1iHu052oc1x0m4=; b=NtO2TJoW2DmuyMqZ06HBHhBHSeVjIzLw0gWKlZ/Ktb2SIto12052dKf/Obc4R/DFZ0 8wVThv1Vp9Ntm/KK3fYUCvnTmFbjJiOAH1fOv20pAVWjYBA82Zg8LFGT2lYpqUzr42rS ZIK4YDKXCl1ze/Yf3oLqKVdMvhlTOCDMHILMA1LKLcmyblICjreqcpWLpc/b8VV60LCW +pd3l5g3rwoKKoxObap27Q/l9oLHiFTs+IIeV+gUCONKoJlfEsXKVQFLj0rUAMhSAlHu ki4fp2jQVJ3geqSpxhgU1tKA7fLhz3oY2cXkKH/AIzAzHMbyLUwCwFtkTXs9JCH1s+n5 rTEQ== X-Gm-Message-State: ABUngvdm4CNDSnnPp0154PphhKOj6B0TsBkSuLYcQeRxCa0eyb5yvjhV+FnT75XwxpDlug== X-Received: by 10.99.95.151 with SMTP id t145mr2776407pgb.131.1479458046779; Fri, 18 Nov 2016 00:34:06 -0800 (PST) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.157.15.106 with SMTP id 97ls6513649ott.11.gmail; Fri, 18 Nov 2016 00:34:05 -0800 (PST) X-Received: by 10.55.49.203 with SMTP id x194mr10130507qkx.93.1479458045920; Fri, 18 Nov 2016 00:34:05 -0800 (PST) Original-Received: from mail-qk0-x242.google.com (mail-qk0-x242.google.com. [2607:f8b0:400d:c09::242]) by mx.google.com with ESMTPS id n54si2117950qta.44.2016.11.18.00.34.05 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 18 Nov 2016 00:34:05 -0800 (PST) Received-SPF: pass (google.com: domain of tartanllama@gmail.com designates 2607:f8b0:400d:c09::242 as permitted sender) client-ip=2607:f8b0:400d:c09::242; Original-Received: by mail-qk0-x242.google.com with SMTP id n204so30581212qke.2 for ; Fri, 18 Nov 2016 00:34:05 -0800 (PST) X-Received: by 10.194.60.195 with SMTP id j3mr5014185wjr.149.1479458045474; Fri, 18 Nov 2016 00:34:05 -0800 (PST) Original-Received: from [10.54.100.137] ([185.34.9.74]) by smtp.googlemail.com with ESMTPSA id f126sm2060605wme.22.2016.11.18.00.34.04 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 18 Nov 2016 00:34:04 -0800 (PST) In-Reply-To: <7c87350a-7ac2-489b-b107-ea25a7bd6c74@isocpp.org> X-Original-Sender: tartanllama@gmail.com X-Original-Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com; spf=pass (google.com: domain of tartanllama@gmail.com designates 2607:f8b0:400d:c09::242 as permitted sender) smtp.mailfrom=tartanllama@gmail.com; dmarc=pass (p=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:29454 Archived-At: If I understand your code correctly, you could implement it with the current fold expression proposal like this: template void foo(Ts... ts) { ((std::cout << ts), ...); } On 18/11/16 08:14, z.p.gaal@gmail.com wrote: > During metaprogramming lots of dummy functions have to be implemented to process tuples and/or variadic templates. I don't know too much about proposal submission and I don't have so deep knowledge of the language either. > But it'd be great to have expressions something like > > template > void foo(T... a) { > for...( Ti ai : a ) { > std::cout << a > } > } > > It'd make the code more readable and remove lots of index_sequence based hacks. > > Is there any similar proposal already. What do you think of this idea? > > thanks Gzp > -- 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/110fecc1-a731-f6ad-fa8d-cfe2cb36faaa%40gmail.com. .