220 41209 article Path: news.gmane.org!.POSTED!not-for-mail From: Gareth Lloyd Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Make the many times redundant auto optional Date: Mon, 3 Dec 2018 16:27:55 +0000 Lines: 89 Approved: news@gmane.org Message-ID: References: <5A1317DB-205E-49B7-B641-8D1E923F0907@gmail.com> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: multipart/alternative; boundary="00000000000046d780057c20a2f2" X-Trace: blaine.gmane.org 1543854363 30790 195.159.176.226 (3 Dec 2018 16:26:03 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Mon, 3 Dec 2018 16:26:03 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBCTJTSELJQIJRM4V4ACRUBCVNZKEU@isocpp.org Mon Dec 03 17:25:59 2018 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-wr1-f71.google.com ([209.85.221.71]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1gTr2k-0007r3-Tp for gclcip-std-proposals@m.gmane.org; Mon, 03 Dec 2018 17:25:58 +0100 Original-Received: by mail-wr1-f71.google.com with SMTP id q18sf11223177wrx.0 for ; Mon, 03 Dec 2018 08:28:09 -0800 (PST) ARC-Seal: i=2; a=rsa-sha256; t=1543854489; cv=pass; d=google.com; s=arc-20160816; b=rnAIPuTJGTQoIhItGXAosDziM61d9rgG8JRWDbRNOqinr79rW+EUnLlF4+revgZ84z f6RvQGNivuCgWifZ8dY0YWYPNEYbeQbhisv9KZLBuwsfapeQtYyV+7Ke8ak5hUccwoSY DalFLgrve49yJiVm1bfblp12mHj/rWLWMjfuRTw11v03TZJ9xdTB8wgY0ATteb25HCR3 S8VYTLNq1tbtoKTII+P7xYHWI4U/y8FiBnbxJ6MZdg6H8Yf23ORbXXiEQoiAhuy1l5hq aIzZgbsQlf5bvetSD3Au2+u3PDX2Qh2q/tS6vhVlrLhM+UyWc4C3zfJn2MSLRjPuHbIq 5Fdg== ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-unsubscribe:list-subscribe:list-archive:list-help:list-post :list-id:mailing-list:precedence:reply-to:to:subject:message-id:date :from:in-reply-to:references:mime-version:dkim-signature; bh=ygvv4HAf58ONw/Hswdr7hwaWvTuG/OL5utJqoGA86p4=; b=cKPNwnnwgSABYyO6JyntsSTEfDGomf+IJ85O+zhkEtgkK22SVFEWCR9tvNSW/6n6Va vvOJIqsk4LvBnROtMX4yiOVA0ZwZ9LxNnpcgLJkyydNXthjg/P/MP5nrIzhd7gHyWBLv Mf3jrBdkaRpGoHY+BhWA0rUR8P4Mp0S6cQcjoBpsxsrUlBDIRXKEW36fzuaqcxDhl/zj dWN2/n/s1J0H8w5334FMjnbkhlbvQSiz+n5KeyBDYo+XbHF658EmTQ/3akJXuVLHwv/v pDwzMI0DmRb6AmKP+sDJkvV2/qEh/iNnw6HRslbNjjoilIt5jei1qV0qwzfcb+0vfjAq hAgA== ARC-Authentication-Results: i=2; mx.google.com; spf=pass (google.com: domain of gareth.andrew.lloyd@gmail.com designates 209.85.220.41 as permitted sender) smtp.mailfrom=gareth.andrew.lloyd@gmail.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=isocpp-org.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :x-original-sender:x-original-authentication-results:reply-to :precedence:mailing-list:list-id:list-post:list-help:list-archive :list-subscribe:list-unsubscribe; bh=ygvv4HAf58ONw/Hswdr7hwaWvTuG/OL5utJqoGA86p4=; b=shLegEdR1ofvzfa/DPCANeXnu5Kc0wbHJylxzImvTkSWjk5wukJYka+9H6aHqLW0mE a1I1n/tgVEHzComRXNmL57Iui2YomqYTmgCiqbbyE8IsYWkxEekwJDwU7iYod5HRqd2D dl4ydHH57fA9cegyPbVciakE3XIhLkGRFN1jKqNUY3reyG57E85tPDY2LAVMfrKkZzJ3 w8RzPf1rtSd9TSkIKYTqqd2iN/ZS9Rv68x3+26Wl67twH2cE8O0u2hTjmRUTnUE3Rd7B Gj5YKMb/+vDQucczI36vTwfjEbltidu/x1quMrLdUk2oOS0HTgEWpH2gBq6lGVIohrb+ DTcA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject: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=ygvv4HAf58ONw/Hswdr7hwaWvTuG/OL5utJqoGA86p4=; b=LecMOCXZmBWB/q/oZavvPy1fnO/mDTMX7tuHD+bqC2qP/J7WATa2+c911zLGFNdOCw +syah36nBAC//fgGlI0/b47MpcS3ud7yH2GCvxW17cAkxjJvy60oPeLedeGkb7j2URoc 2HNqUQ4tXD/ZUCw9Z4HUSVkna9Zl/0o5XWrtsb2v6+YbygYz08eWYJvXQ1ZuFQezmMJh xoQM2OU1cV4sswpmEfW+2Qwtgh0T3rfmerhKVjCXHKowX922nH2TufYpmwy9N7XR//fc 0cl+3/NSM3so+9zq1GeIK1B7sTkpqpZIKrlDKiFRkz/5cjZ5w/9e4Lu3x0phgXD2+yuJ kzGA== X-Gm-Message-State: AA+aEWZcsBtrWW/o7761BOs7ZhoVACkW7TjshdVSia8Yp241Tp4QHWMw 3D9ZYQQ+LnCuGHSrSa200+A= X-Google-Smtp-Source: AFSGD/X7cEpcBAJTzKqmSlJ/m3nfzHij8AtA7BFQku2hEiXKRkPjA4ocfB/aDQSn5cdAwm9XQrQV3w== X-Received: by 2002:a1c:6708:: with SMTP id b8mr1643555wmc.5.1543854489619; Mon, 03 Dec 2018 08:28:09 -0800 (PST) X-BeenThere: std-proposals@isocpp.org Original-Received: by 2002:adf:afca:: with SMTP id y10ls4341845wrd.4.gmail; Mon, 03 Dec 2018 08:28:08 -0800 (PST) X-Received: by 2002:a05:6000:10d1:: with SMTP id b17mr14656849wrx.306.1543854488323; Mon, 03 Dec 2018 08:28:08 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1543854488; cv=none; d=google.com; s=arc-20160816; b=CtRLTCAJ9/7nbpI3wR5nqSN7psZP65lrkcc3xHPoZn03RNfP7akQsEFNFRTPC/QdwR 9/8+nxmH3JJDmBwQK63TZOV1C3VfN0k3/hHRjF/M+G1tYdbsXfWwkU5pmREKL+/F1TSO uF6W5jqwdCrSSbBFVjuwRARXfF79Fadtsqipl15DIopDa7sVAJ0knPruoJAwrmJI6p3L KJTS7VY7EOs7HI0vZSB9M+s6GBicHFpJFvO90R41jEQ12GOYLNfQIP5G1/wWP8FPhObD 6HjGRtcS8kjQ6IISBA3Iaf6ullGYPuIvZ+sLoM8Z7G9ENYaroOZfq1sceTCI8x5AT/7Z 0r4g== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=to:subject:message-id:date:from:in-reply-to:references:mime-version; bh=yv2anjvEzb6KGWujjjXGwgJl5ANNs5IY3PuIbOiOfAg=; b=ytdQv9nYOzAt5WWhyfyN4ODgvMeTIIaCMboaaoaSvPi7Eesm82mRvHV8lzltUJczdV bS21m1wOL7EQXcO9Pr+wITqzi+FJrz1S07YHJwHh/JE7ndIgmIfQ15vdEV4C8AnKqU1l tkoX8NtiOgAN+l73LILJFPV430HFe3RRDpX9Q5dMoRDUm7dEj3ZXAJFzCkB0OUsqc1+m K0UXFDhKL6MN6bf0n83N+XEBCfZ6i/fGYJgGlCZD2PGXuXuR/GaRa1auM6fzBII+rz1j IR041U9jQlgEXDaTzCQ0nVzFNE/VHE6EskQz41v4vj0rh+u3LSqTTSbBF3qT0nBHQgzI kdaw== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of gareth.andrew.lloyd@gmail.com designates 209.85.220.41 as permitted sender) smtp.mailfrom=gareth.andrew.lloyd@gmail.com Original-Received: from mail-sor-f41.google.com (mail-sor-f41.google.com. [209.85.220.41]) by mx.google.com with SMTPS id i185sor2740055wmg.20.2018.12.03.08.28.08 for (Google Transport Security); Mon, 03 Dec 2018 08:28:08 -0800 (PST) Received-SPF: pass (google.com: domain of gareth.andrew.lloyd@gmail.com designates 209.85.220.41 as permitted sender) client-ip=209.85.220.41; X-Received: by 2002:a1c:6382:: with SMTP id x124-v6mr9513910wmb.145.1543854486900; Mon, 03 Dec 2018 08:28:06 -0800 (PST) In-Reply-To: X-Original-Sender: gareth@ignition-web.co.uk X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of gareth.andrew.lloyd@gmail.com designates 209.85.220.41 as permitted sender) smtp.mailfrom=gareth.andrew.lloyd@gmail.com 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:41209 Archived-At: --00000000000046d780057c20a2f2 Content-Type: text/plain; charset="UTF-8" On Wed, 28 Nov 2018 at 02:54, Raymund Hofmann wrote: > The reason on SE it was rejected seems weak for me. > for ( for-range-declaration : for-range-initializer ) statement for-range-declaration: attribute-specifier-seq opt decl-specifier-seq declarator attribute-specifier-seq opt decl-specifier-seq ref-qualifier opt [ identifier-list ] IMO it would be unreasonable to change the grammar here. Stuff like attribute-specifier-seq are fine to make optional because they are easily identified by the next characters ''[[" or "alignas(", those can not be confused with decl-specifier-seq. decl-specifier-seq should not be optional it takes more lookahead or backtracking to figure out if decl-specifier-seq was provided or not. This is not just an issue for your compiler but any IDE language support. -- 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/CANgTfEgkerV-21PV1goyvkU8A6AySW2yVyQK5r-APDancQr%2BBQ%40mail.gmail.com. --00000000000046d780057c20a2f2 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
On Wed, 28 Nov= 2018 at 02:54, Raymund Hofmann <hofmannraymund@gmail.com> wrote:
The reason on SE it was rejected seems weak for= me.
=C2=A0
for ( for-range-declaration : for-range-ini= tializer ) statement

=
for-range-declaration:<= /div>
=C2=A0 attribute-specifier-seq o= pt decl-specifier-seq declarator
=C2=A0 attribute-specifier-seq opt decl-specifier-seq ref-qu= alifier opt [ identifier-list ]

IMO it would be= unreasonable to change the grammar here. Stuff like attribute-specifier-se= q are fine to make optional because they are easily identified by the next = characters ''[[" or "alignas(", those can not be con= fused with decl-specifier-seq. decl-specifier-seq should not be optional it= takes more lookahead or backt= racking to figure out if decl-specifier-seq was provided or not. This is no= t just an issue for your compiler but any IDE language support.
=C2=A0

--
You received this message because you are subscribed to the Google Groups &= quot;ISO C++ Standard - Future Proposals" group.
To unsubscribe from this group and stop receiving emails from it, send an e= mail to std-proposa= ls+unsubscribe@isocpp.org.
To post to this group, send email to std-proposals@isocpp.org.
To view this discussion on the web visit h= ttps://groups.google.com/a/isocpp.org/d/msgid/std-proposals/CANgTfEgkerV-21= PV1goyvkU8A6AySW2yVyQK5r-APDancQr%2BBQ%40mail.gmail.com.
--00000000000046d780057c20a2f2-- .