220 40576 <341708ed-e98b-1744-fbdb-5b1036838323@gmail.com> article Path: news.gmane.org!.POSTED!not-for-mail From: Matthew Woehlke Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: against P1274R0 add $ to identifier names Date: Tue, 16 Oct 2018 14:48:18 -0400 Lines: 33 Approved: news@gmane.org Message-ID: <341708ed-e98b-1744-fbdb-5b1036838323@gmail.com> References: <1484cf21-8224-4fb8-457e-8c1e4a3121c2@gmail.com> <10926898.pV5Fg0ApEB@tjmaciei-mobl1> 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 1539715575 29461 195.159.176.226 (16 Oct 2018 18:46:15 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Tue, 16 Oct 2018 18:46:15 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.0 To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBC37LBFWUIFBB5HETDPAKGQEXBKSTFY@isocpp.org Tue Oct 16 20:46:11 2018 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-qk1-f198.google.com ([209.85.222.198]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1gCUM7-0007Yo-5G for gclcip-std-proposals@m.gmane.org; Tue, 16 Oct 2018 20:46:11 +0200 Original-Received: by mail-qk1-f198.google.com with SMTP id 142-v6sf22290qkn.17 for ; Tue, 16 Oct 2018 11:48:22 -0700 (PDT) ARC-Seal: i=2; a=rsa-sha256; t=1539715701; cv=pass; d=google.com; s=arc-20160816; b=x2IJxA1eesVjejNEnucPpnO1e3ZXIakwecvH11GNEaVon7JErwqpet0mmx2Mn38dIR e4VU5rsTd1tbFkxx10UXzH6GB4TNaTjOstYAsUg7PY73h3lzlG/lQo5Fh4xFcWpjK9a8 kmJ6zp01izgYH9CNB+vQztlxJVGvMCyt43g0MC0mG3CbshGkRtWYEhSvrL/1wmlJX1kD OQr/P3Mgx0AK7XyrTWlVJjms8UqdoFjjeMb3K/HaJf8qKZNMT070MuvXTXAVXFjMCiTA nMHzZffFJWO0OPwV2LwWu2HXeGXWpUooE6E/hkXWrAA4lM+k6euYaJ7LBHm/BlWLzA10 W6Qw== 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:content-language :in-reply-to:mime-version:user-agent:date:message-id:openpgp:from :references:to:subject:dkim-signature; bh=0miTw0Ekr89aK7FAIV+tYK1WITvCc5h648rKDMxHH+Q=; b=zQg6Y10UGM3oQCWr+DfaE0N7y5IAbxy7oNvtjt0I4H4zLQjVqewNZUFbOoJg9gVknf b7V3DPlF/W3klfr7vgpKINoaHCwXbMLtfAe26AVhWS4hA9k7FqoHeDZtX2qzP0uMO/Ui 7tq+OTwhuzWacT+cUxU6HLgEs8uPG2mz2uj85ksvp8G7SKXcsFvq4rb8XankXjBLAHz4 1CEoBZRyF4Nd+fU7J9mrUxlEyzOj4/ch4hGgO5Vh4Vu5a7CiXiY4Yp5Y7KRyH4omoqmM TGQbILsUId+xOpjd/HdqPLmur8ba3BXTXm2+BYi4UNZluHyyaONr8d4HTnrppQ7pLZHV vFHg== ARC-Authentication-Results: i=2; mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=jFIxAXtJ; spf=pass (google.com: domain of mwoehlke.floss@gmail.com designates 209.85.220.65 as permitted sender) smtp.mailfrom=mwoehlke.floss@gmail.com; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=isocpp-org.20150623.gappssmtp.com; s=20150623; h=subject:to:references:from:openpgp:message-id:date:user-agent :mime-version:in-reply-to:content-language: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=0miTw0Ekr89aK7FAIV+tYK1WITvCc5h648rKDMxHH+Q=; b=0JedJE2F2dtFJoDU5eePtSqUV9L4TsRVZnuWjAiOoS0Z0xUyLIXOR8cFUrxR2zIbGt dS68nCpbZJ+KR4YvdLkltB1SbRsWT+ZNBzSeGXQJnSgSBNSxz0I4wTmOuaDnp45IyxXL bC3GI+2mZ4SGd6v+rQNRmQF+1re3ckYHs3IXYzJcPVfpm1qaYC/7ZQNFe5eU+9C08DJQ NG1qWFhKv+MADfCL5sbjdhPCK1u9UTVeoBywqv/pS0wBV1jIgT4QP+7eO9kvKRmE/EWU o6FS/QAOD8kWngpNucTIvzN238aR1M6HYrwrnReRRd6iMhMpgDQMM9fmX94uIY/MzN+H ApDA== 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:from:openpgp:message-id :date:user-agent:mime-version:in-reply-to:content-language :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=0miTw0Ekr89aK7FAIV+tYK1WITvCc5h648rKDMxHH+Q=; b=pFvSpDMPCe5NqK4lT54+kdxo3R2vUxzZqR55jHkK/nuIrGl5KowG7XZMasZOaxzFNp 7SYTSvgyaXfBx6mZPX1PkpMNci1RwXz27lUZJnFWwTpxgNliujlR5g4GrNCSo9xkVOJS fpNOhtFeHIbJHW/eeW5nBBI9RNh0GK0CtqZ34ntYOtrWT0UHw04IaBr6hVmhHrqYKYv0 yLvoPRwfcCBnE+YC2bdnmxIzLkf03Td81ofNIRIqOTlaH2sD6nTprOjsGtoApmh36A9G QaderQgvVQt9pFR0tcklz6UtgdNeuqEtoS7nm1hQSg/Hc23bnMuSkTHzzJq1aBZzwEHc X-Gm-Message-State: ABuFfogdeAwIx2n+t1/5RwcBSqAyBu4g6+DE9zcHNQBteggY69SuhFuF 532I1Qsx2LGucJqfVJAnL+JAow== X-Google-Smtp-Source: ACcGV61RP/FqHhs46pZ09qgzcPebkgUpas/aXkYYrtCGKPqR8iIyXNQXRqVqnsc3X9I9RMfIexbtZw== X-Received: by 2002:ac8:4108:: with SMTP id q8-v6mr18865191qtl.17.1539715701635; Tue, 16 Oct 2018 11:48:21 -0700 (PDT) X-BeenThere: std-proposals@isocpp.org Original-Received: by 2002:a37:a18d:: with SMTP id k135-v6ls9345342qke.5.gmail; Tue, 16 Oct 2018 11:48:20 -0700 (PDT) X-Received: by 2002:a37:17e5:: with SMTP id 98-v6mr21294016qkx.42.1539715700568; Tue, 16 Oct 2018 11:48:20 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1539715700; cv=none; d=google.com; s=arc-20160816; b=C0gMSj4iZexMT3WzCFxcYpqg0k/BslpM2Glw6su7INLyB+WLHk7eLFtqfIj8htrwhV cJRqYL0y1/DkfFpP2b6SMeS2oWKEDEqGnlDG6IQLmTgn4CA/cZEDe9148PD4d0Nqw+T7 uu5Vsjp9QbGAWYGpKTPFB/MUeFu6aw8bDw9zIi0tqrf2U50qK0UvSaU6Vzpq8QQloT3B 5arizmobxPbcjHUWVN+UYcZTgy+3h21WZnk4zfjCySWrG4UBT1Hk5WcbBdpssE2uT8XN SBJQiiQ+wRbJTSXIqZOjb1jIDXTL+WDzjHUQTXoLEq/64mjKhc4egRHLrJGeRkYuOm4X Am7w== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=content-transfer-encoding:content-language:in-reply-to:mime-version :user-agent:date:message-id:openpgp:from:references:to:subject :dkim-signature; bh=6tebM/prKRBEhLGThnrJjQZ8yxs+cAi/DrhM4sEcFWY=; b=LREPsWrzsWhsGpjwUqmhPKnkwUtwNPrUa8ylWeOPiGF+Dp9VqPqVxrdcHwrNXTTsJw 4wbIlQ36U//xWcELj+GaZZjPWtbAUOm0km8L2zc7BnsNtu0gaMvvBTzqUZxyGGODMzB0 8v4pj6HmsEnNox4G5RybR9paFjhHHqAEHBMmgGjW4XjkW2leiMZm8lK3BYd2J3RvlRFY NIXxTqw2vSv2qUchDq32R5UxSj5N5f6+dW5Cb5k/zPWCf2zr2sYTFJVthCWylrIidR17 JNzvpMCYyyS0IJcpgmqWn36b2u6IK7fhHw1CHfQETlHuJTTWhlLJ3z60JgsVjRL+EloM S+Rw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=jFIxAXtJ; spf=pass (google.com: domain of mwoehlke.floss@gmail.com designates 209.85.220.65 as permitted sender) smtp.mailfrom=mwoehlke.floss@gmail.com; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Original-Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id x13sor6852051qvc.4.2018.10.16.11.48.20 for (Google Transport Security); Tue, 16 Oct 2018 11:48:20 -0700 (PDT) Received-SPF: pass (google.com: domain of mwoehlke.floss@gmail.com designates 209.85.220.65 as permitted sender) client-ip=209.85.220.65; X-Received: by 2002:a0c:a425:: with SMTP id w34mr6572871qvw.160.1539715700132; Tue, 16 Oct 2018 11:48:20 -0700 (PDT) Original-Received: from gryphon.kitware.com (tripoint.kitware.com. [66.194.253.20]) by smtp.googlemail.com with ESMTPSA id v54-v6sm18355868qtc.81.2018.10.16.11.48.19 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 16 Oct 2018 11:48:19 -0700 (PDT) Openpgp: preference=signencrypt In-Reply-To: Content-Language: en-US X-Original-Sender: mwoehlke.floss@gmail.com X-Original-Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=jFIxAXtJ; spf=pass (google.com: domain of mwoehlke.floss@gmail.com designates 209.85.220.65 as permitted sender) smtp.mailfrom=mwoehlke.floss@gmail.com; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=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:40576 Archived-At: On 16/10/2018 14.32, Nicolas Lesser wrote: > On Tue, Oct 16, 2018 at 8:33 PM Thiago Macieira wrote: >> If we allowed >> >> if (empty?(y)) >> >> then the parser would need to know that it's not a case of the ternary >> operator, so it needs to parse a lot before coming to that conclusion. > > Not really. There is still the "max-munch" rule. Which is why that would > break a bit of code. Your above snippet would be ill-formed with the > change, as there is a colon without condition operator. If you're saying (as I think you are) that keeping the grammar sane would mean that an existing identifier followed by `?` with no intervening whitespace would, under the proposal, include the `?` as part of the identifier, I think that's a clear non-starter. I'd be surprised if there isn't a non-trivial amount of existing code that would be broken by such a change. Something else that just occurred to me... at least in the absence of non-ASCII characters, C++ identifiers all match /\w+/. Changing that could have interesting ramifications... -- Matthew -- 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/341708ed-e98b-1744-fbdb-5b1036838323%40gmail.com. .