220 31838 <58DAA2A6.70508@gmail.com> article Path: news.gmane.org!.POSTED!not-for-mail From: Matthew Woehlke Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: This variable should not be named: an identifier (not) to remember Date: Tue, 28 Mar 2017 13:51:34 -0400 Lines: 55 Approved: news@gmane.org Message-ID: <58DAA2A6.70508@gmail.com> References: <985b9b2a-c734-45eb-95f4-db4dc0d309a1@isocpp.org> <14211602.1P4LjlnQMh@tjmaciei-mobl1> <8028901.3vRB6vfJZY@tjmaciei-mobl1> <58DA9D90.6020207@gmail.com> <57461565-aaec-44d2-becd-9abd76ebeb76@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 Content-Transfer-Encoding: quoted-printable X-Trace: blaine.gmane.org 1490723512 23356 195.159.176.226 (28 Mar 2017 17:51:52 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Tue, 28 Mar 2017 17:51:52 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.1.0 To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBC37LBFWUIFBBNWF5LDAKGQECHKJP4A@isocpp.org Tue Mar 28 19:51:47 2017 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-it0-f70.google.com ([209.85.214.70]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1csvHV-0005NX-Id for gclcip-std-proposals@m.gmane.org; Tue, 28 Mar 2017 19:51:45 +0200 Original-Received: by mail-it0-f70.google.com with SMTP id e75sf19646876itd.16 for ; Tue, 28 Mar 2017 10:51:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=isocpp-org.20150623.gappssmtp.com; s=20150623; h=subject:to:references:newsgroups:from:message-id:date:user-agent :mime-version:in-reply-to:content-transfer-encoding :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=UjTzUpTUWCbTlrY+RajNm5xuU9sewKvsHdtqc9kgAuM=; b=vFarQaHmDGDZ23xV4TICHCSJ1SyH0n9B1YkM9Oe8V53WST1GdilwuImR8xkvgt0Yq4 BFQvHUYKzg1RBb1D6sXkl0xqgQYpSSI0cfUdoJVav4gdpnFg5+EsPsAchl4nlpE8FjYK 3UtM5Vd0ZDZng3VdyZohCcPdcEib/Anh9fLvgN0A+GcmmpskmDsEshSuUhsTIIczSAQr eVKwJV3/snXsi6lSmYPLIQEs1dbyUUT/FucaJLLhExwoYZeG5zr954YMsyqFcGHiaddB sLTdtgmzlKmrrK9Hfw7KPTA64yK1GaOnmDupB8ith5s1KjyLaDwh+eXoIruJKkS X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:newsgroups:from:message-id :date:user-agent:mime-version:in-reply-to:content-transfer-encoding :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=UjTzUpTUWCbTlrY+RajNm5xuU9sewKvsHdtqc9kgAuM=; b=KlbbVOGTyWwO82B7ZxBCfB9zOR9wEk42QfIt9hf3Z5ZETd/qVjEnRjFNNGFYSIvbKB aXDCXBJrtbsDJudV6rDqRZyOxJFvuCm0TGn6pQU3gw0Me6KuJlh6tDL5sYSVASGlHoEf ahB4QchDMT+Tzu+A6QyPwU1BE2g3rA3ukfuhTuzgEnFqUnqktqzpWzInAoNUTHlwI+qp zu/vBXzrgqKEWGldJOdgjD9cv6/axt5qpPWRSg7tCVlanE+bLu0d7VIOkQhJ1GF1+GBY ttInidAi7BTaT7ONyeprdEub2HWCaPKjdipbEzxawyX9uBzGFqA1mo9eMyF X-Gm-Message-State: AFeK/H09ojO1p1fUFjj9IyWsgZuGx+NYQYPDqUwSi8UGZ6F5ntmu/k1VYgLPhZNCqqBkWw== X-Received: by 10.36.127.19 with SMTP id r19mr4486766itc.33.1490723511424; Tue, 28 Mar 2017 10:51:51 -0700 (PDT) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.157.34.21 with SMTP id o21ls810145ota.12.gmail; Tue, 28 Mar 2017 10:51:50 -0700 (PDT) X-Received: by 10.202.76.148 with SMTP id z142mr6144360oia.114.1490723510489; Tue, 28 Mar 2017 10:51:50 -0700 (PDT) Original-Received: from mail-ot0-x22a.google.com (mail-ot0-x22a.google.com. 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[66.194.253.20]) by smtp.googlemail.com with ESMTPSA id 65sm1974101otq.34.2017.03.28.10.51.35 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 28 Mar 2017 10:51:35 -0700 (PDT) Original-Newsgroups: gmane.comp.lang.c++.isocpp.proposals In-Reply-To: <57461565-aaec-44d2-becd-9abd76ebeb76@isocpp.org> X-Original-Sender: mwoehlke.floss@gmail.com X-Original-Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com; spf=pass (google.com: domain of mwoehlke.floss@gmail.com designates 2607:f8b0:4003:c0f::22a as permitted sender) smtp.mailfrom=mwoehlke.floss@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:31838 Archived-At: On 2017-03-28 13:39, Nicol Bolas wrote: > On Tuesday, March 28, 2017 at 1:29:57 PM UTC-4, Matthew Woehlke wrote: >> On 2017-03-28 13:03, Thiago Macieira wrote:=20 >>> On ter=C3=A7a-feira, 28 de mar=C3=A7o de 2017 09:53:51 PDT Zhihao Yuan = wrote:=20 >>>> auto [__, __] =3D get_tuple(...);=20 >>>> >>>> should be physically equivalent to=20 >>>> >>>> get_tuple(...);=20 >>>> >>>> thus, the result object is dropped on the floor.=20 >>> >>> This should be equivalent to:=20 >>> >>> auto __ =3D get_tuple(...);=20 >> >> I would argue it should be equivalent to:=20 >> >> auto __magic__ =3D get_tuple(...); // note: same as today=20 >> auto __ =3D get<0>(__magic__);=20 >> auto __ =3D get<1>(__magic__);=20 >=20 > The question is this: will people actually want side effects of ignored= =20 > parameters? Or more to the point, why exactly would you want those side= =20 > effects? Consistency? // Same? Uh... no? auto __ =3D expr; auto [__] =3D expr; // Same? I hope so? auto [__] =3D expr; auto x =3D expr; auto __ =3D get<0>(x); // Same? Better be! auto [y] =3D expr; auto x =3D expr; auto y =3D get<0>(x); --=20 Matthew --=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/58DAA2A6.70508%40gmail.com. .