220 9911 article Path: news.gmane.org!not-for-mail From: Johannes Schaub Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: auto variable templates? Date: Wed, 19 Mar 2014 20:14:59 +0100 Lines: 55 Approved: news@gmane.org Message-ID: References: <878usaa8hz.fsf@euclid.axiomatics.org> <93E854CB-24C9-49ED-BE88-1A43D0FD715A@gmail.com> <877g7qm4yd.fsf@euclid.axiomatics.org> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 X-Trace: ger.gmane.org 1395256494 32215 80.91.229.3 (19 Mar 2014 19:14:54 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 19 Mar 2014 19:14:54 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBCQPNCEZSQNBBNGZU6MQKGQE54GC73Y@isocpp.org Wed Mar 19 20:15:04 2014 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-pa0-f71.google.com ([209.85.220.71]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1WQLx8-0004hx-E4 for gclcip-std-proposals@m.gmane.org; Wed, 19 Mar 2014 20:15:02 +0100 Original-Received: by mail-pa0-f71.google.com with SMTP id kq14sf23571113pab.2 for ; Wed, 19 Mar 2014 12:15:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlemail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from: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:content-type; bh=AlosVTnBbL+YTfFmq8QVZpZgaI+GzFuPnX0baDZwewQ=; b=gCWf3RygHHTxWPPiYs72JU5J5Azi2xYVxR2Ghc5K1ZXqN85Rmppk9mVMQTjwFlyi4b D5ve7yuNkYPF2OAqrWxyuYVxRWpreYnyOd/pcldGYtpbUKu2qgEW/HMnso4McsjGUpHY nkjBtwhG9bGDY1uRgP0w+yP4ui0726Oh2Vcspmk6xl/froBQDYftp3wo/XyW2GgrKmf6 jkOELQp/KRQS4oV77usIv2sr0TcR8NOSoItCFMVXjgPSEB+NvIHakalxGwNc8dVKxFt5 S8UEqgIuIrczUfW4+/0DqL7YYAUmauqcPuu3kLogeeBukZIFakdsTCzztMdOG8RjV9mp h66A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from: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:content-type; bh=AlosVTnBbL+YTfFmq8QVZpZgaI+GzFuPnX0baDZwewQ=; b=dXel32MQxrmnd8UYps8pW5E4kAgcmXAqFmxL8FWgN7CaFiPy8ZrtajmMsoZZvdBAq5 MhEKlh+9j9fZ5c8CAb8cH75KjIzrPRLSoFNIRP52RbiDi9ZF/GUDvEnKSs60FHvP1yZ2 zHrclCmIpLNaB5qPds5tjHZmBPuMBdEb0dJObduI1w9QS2grSTkNw8KmY7lAJ0oyTKbY BFbtNPrI+ub+8N8KumibG8tik88ruVewzczye6W0OOxyXE+hVioPij92nD0OajRTOvr+ yt0mRiRWelPMtVkFtFx2N/5igEfWBT6OdFlId5SZ3m+fQYFopjdPGDklhT36ROyRkR5C 6p+g== X-Gm-Message-State: ALoCoQlBSr/x4bHbm8GaupAAq8nfMaVSNnW7jWq6q6MSGDs7WN0h8EjVCubnBg7ESfrrH0w9QvzD X-Received: by 10.66.102.36 with SMTP id fl4mr15093236pab.20.1395256501308; Wed, 19 Mar 2014 12:15:01 -0700 (PDT) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.50.118.99 with SMTP id kl3ls566688igb.3.canary; Wed, 19 Mar 2014 12:14:59 -0700 (PDT) X-Received: by 10.66.232.68 with SMTP id tm4mr41440228pac.114.1395256499926; Wed, 19 Mar 2014 12:14:59 -0700 (PDT) Original-Received: from mail-pd0-x232.google.com (mail-pd0-x232.google.com [2607:f8b0:400e:c02::232]) by mx.google.com with ESMTPS id dg5si5240485pbc.337.2014.03.19.12.14.59 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Wed, 19 Mar 2014 12:14:59 -0700 (PDT) Received-SPF: pass (google.com: domain of schaub.johannes@googlemail.com designates 2607:f8b0:400e:c02::232 as permitted sender) client-ip=2607:f8b0:400e:c02::232; Original-Received: by mail-pd0-f178.google.com with SMTP id x10so9065581pdj.23 for ; Wed, 19 Mar 2014 12:14:59 -0700 (PDT) X-Received: by 10.67.2.106 with SMTP id bn10mr41552002pad.38.1395256499788; Wed, 19 Mar 2014 12:14:59 -0700 (PDT) Original-Received: by 10.68.216.97 with HTTP; Wed, 19 Mar 2014 12:14:59 -0700 (PDT) In-Reply-To: <877g7qm4yd.fsf@euclid.axiomatics.org> X-Original-Sender: schaub.johannes@googlemail.com X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of schaub.johannes@googlemail.com designates 2607:f8b0:400e:c02::232 as permitted sender) smtp.mail=schaub.johannes@googlemail.com; dkim=pass header.i=@googlemail.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:9911 Archived-At: 2014-03-19 19:14 GMT+01:00 Gabriel Dos Reis : > David Krauss writes: > > | On 2014-03-16, at 3:49 PM, Gabriel Dos Reis > | wrote: > | > | The general model of C++ templates, since day 1, is that if decl > | is a > | valid declaration, then > | > | template decl > | > | is also a valid declaration. > | > | > | Well, Johannes' code is specifically a counterexample to that rule, > | because the error is in the parameter-list. > > I am not sure why that is a counter example: if the parameter is > non-sensical, it can't be a declaration. > I was playing devil's advocate. You are saying that the following is a template template constexpr auto X = 42; But the "decl" is non-sensical, because while it is allowed to put "auto" in the declaration of a variable, it is not allowed in the declaration of a variable template. > | It seems fairly obvious that an invalid template parameter declaration > | is diagnosed when translating it, > > Yes, which is why I don't understand why it is a counterexample. > Yes, I agree to this. > | not at instantiation. If his code > | exposes a defect, it belongs to name lookup, not the instantiation > | process. > > I am not quite sure what you think is the defect. > I don't understand this sentence either. -- --- 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. 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