220 5344 article Path: news.gmane.org!not-for-mail From: =?ISO-8859-1?Q?Daniel_Kr=FCgler?= Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Allowing any integral type as an argument for user defined operators Date: Mon, 8 Jul 2013 19:37:35 +0200 Lines: 53 Approved: news@gmane.org Message-ID: References: Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Trace: ger.gmane.org 1373305058 25715 80.91.229.3 (8 Jul 2013 17:37:38 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Mon, 8 Jul 2013 17:37:38 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBCT7RVFA4QORBYHR5OHAKGQE4FY3K2Y@isocpp.org Mon Jul 08 19:37:40 2013 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-bk0-f72.google.com ([209.85.214.72]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1UwFNb-0000nZ-Sr for gclcip-std-proposals@m.gmane.org; Mon, 08 Jul 2013 19:37:39 +0200 Original-Received: by mail-bk0-f72.google.com with SMTP id jc3sf4602324bkc.11 for ; Mon, 08 Jul 2013 10:37:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=x-beenthere: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:x-google-group-id :list-post:list-help:list-archive:list-subscribe:list-unsubscribe :content-type:content-transfer-encoding; bh=1PPI2ST8PPwJNfB0TbxYT4XAqBwqOCdemQocBPW1Wuk=; b=TUL+cCBALSZB8K+VHLUeaqGozQwloJHAGBd+keXPrxcs2mYgSuRW1Guedyt5kmUAo6 7VCiP4R19oj9zQ4DyhH9viWe2NSB0LSt7y+LoPjTnIUjNozRE6pVKZ/TJzoUhxuwQOP4 JKiWqJjTsartIb1CdNZf/t+wFA9MxRbn/dLcKBBhdVNB7DxVsNcAW/rcoCiXvt23SIyJ dEvPVZgeIpOWVmcmbfC02t4SCruy7jFQeJ5Dn6xwRI2Bvn9YgGVC0ENRP+1CofO3Oqvp fKoO9J7SyDyzlPatqu15rUsaMYe17WiMQ+M/dnUfz2+bkYkE5XFR05VFBnVPQ03q16CF 8JCA== X-Received: by 10.180.36.211 with SMTP id s19mr19838960wij.1.1373305059289; Mon, 08 Jul 2013 10:37:39 -0700 (PDT) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.181.12.101 with SMTP id ep5ls2215921wid.15.canary; Mon, 08 Jul 2013 10:37:35 -0700 (PDT) X-Received: by 10.194.93.74 with SMTP id cs10mr12938132wjb.9.1373305055878; Mon, 08 Jul 2013 10:37:35 -0700 (PDT) Original-Received: from mail-we0-x22a.google.com (mail-we0-x22a.google.com [2a00:1450:400c:c03::22a]) by mx.google.com with ESMTPS id lm2si14754809wic.68.2013.07.08.10.37.35 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Mon, 08 Jul 2013 10:37:35 -0700 (PDT) Received-SPF: pass (google.com: domain of daniel.kruegler@gmail.com designates 2a00:1450:400c:c03::22a as permitted sender) client-ip=2a00:1450:400c:c03::22a; Original-Received: by mail-we0-f170.google.com with SMTP id w57so3976917wes.29 for ; Mon, 08 Jul 2013 10:37:35 -0700 (PDT) X-Received: by 10.180.38.45 with SMTP id d13mr12138614wik.62.1373305055531; Mon, 08 Jul 2013 10:37:35 -0700 (PDT) Original-Received: by 10.216.82.66 with HTTP; Mon, 8 Jul 2013 10:37:35 -0700 (PDT) In-Reply-To: X-Original-Sender: daniel.kruegler@gmail.com X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of daniel.kruegler@gmail.com designates 2a00:1450:400c:c03::22a as permitted sender) smtp.mail=daniel.kruegler@gmail.com; dkim=pass header.i=@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:5344 Archived-At: 2013/7/6 Micha=C5=82 Dominiak : > Today I came across a really silly problem - you cannot take `uint64_t` a= s > an argument of a user defined operator, because it's commonly a typedef f= or > `unsigned long`, not `unsigned long long` - even though they are both 64 = bit > on most sane ABIs, you cannot use `uint64_t` as type of `operator""`. I h= ope > we all agree it's a silly situation. > > So, I would like to propose to allow `operator""` use any integral type a= s > its argument type. > > There obviously could be a problem of the parameter being bigger than > `numeric_limits::max()`, which can be solved by issuing an error, l= ike > here: > > constexpr uint64_t operator""_foo(uint8_t); // limit X in X_foo to range = of > 0..255 > auto bar =3D 256_foo; // error: integer constant is too large for its typ= e > > And we'd also get free limit checking as a nice side effect. Thoughts? > > PS If the fact you can only use `unsigned long long` has some deeper > reasoning I fail to see, I would welcome any explanation for it, but, as = I > said, I fail to see any benefits of disallowing integral types other than > `unsigned long long` (or "the biggest integral type available"). Presumably there is some overlap with the existing core language issue http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#1266 - Daniel --=20 ---=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. Visit this group at http://groups.google.com/a/isocpp.org/group/std-proposa= ls/. .