220 19958 <13312961.n5JFXrPRMR@tjmaciei-mobl4> article Path: news.gmane.org!not-for-mail From: Thiago Macieira Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Address of a reference: determining the value category of what it refers? Date: Fri, 21 Aug 2015 21:06:23 -0700 Lines: 78 Approved: news@gmane.org Message-ID: <13312961.n5JFXrPRMR@tjmaciei-mobl4> References: <76fe342f-3342-4355-af20-1c41b21e54aa@isocpp.org> <3183929.eXnTES4BH3@tjmaciei-mobl4> 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 1440216395 10806 80.91.229.3 (22 Aug 2015 04:06:35 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sat, 22 Aug 2015 04:06:35 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBCB4TK757YBRBRHK36XAKGQEMIJW7RA@isocpp.org Sat Aug 22 06:06:30 2015 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-lb0-f199.google.com ([209.85.217.199]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1ZT04b-0000kF-Hh for gclcip-std-proposals@m.gmane.org; Sat, 22 Aug 2015 06:06:29 +0200 Original-Received: by lbbpd10 with SMTP id pd10sf25476718lbb.3 for ; Fri, 21 Aug 2015 21:06:29 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:subject:date:message-id:user-agent :in-reply-to:references:mime-version:content-transfer-encoding :content-type: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=qrXBsRYNGKNmNZ74clX8BwdewnQeZ8SOTvOLGIEuXjI=; b=mlI3EfSReYBXLR2IzoxC/I3WbUUsxPhR7PQzy0SYTVIPViM3BCUYOFgxW5QdWAyxRe w2ak67U7wf6+F/32GTsCm185COkzuLJTcXIl8Nf90cJUESIxtVJhPIb+LFoNXP+ffjEN IknLFgZ2vs8VwYMzUx5qZjPQ8tnLzA559sqpfHlAZ0muXOqBb6/RgsVeOZ1SjM2cNJQc u7WxjNPxNcLKqOggRLhj1XLIshBEJM5lFvjSFnZoSZEfzxW+a0joAoXZ2OIoW7oVQSU7 upslVlac1FHhMc77L6ChrQvvDToKiiLziijHKkzKlzRifeHl685hM20Y4 X-Gm-Message-State: ALoCoQl3G9wVK/wTRZapjDJmpdon6+BhRZA39J7Y4Jhs8wQflY+5qOixHRav+bpxdo1AERzxovKk X-Received: by 10.112.173.230 with SMTP id bn6mr3250838lbc.15.1440216389176; Fri, 21 Aug 2015 21:06:29 -0700 (PDT) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.180.100.227 with SMTP id fb3ls473357wib.23.canary; Fri, 21 Aug 2015 21:06:28 -0700 (PDT) X-Received: by 10.180.105.36 with SMTP id gj4mr11637175wib.64.1440216388154; Fri, 21 Aug 2015 21:06:28 -0700 (PDT) Original-Received: from gondolin.macieira.info (gondolin.macieira.info. [2a01:4f8:d13:f81:21c:14ff:fe01:12a3]) by mx.google.com with ESMTP id gy1si2873563wib.1.2015.08.21.21.06.27 for ; Fri, 21 Aug 2015 21:06:27 -0700 (PDT) Received-SPF: pass (google.com: domain of thiago@macieira.org designates 2a01:4f8:d13:f81:21c:14ff:fe01:12a3 as permitted sender) client-ip=2a01:4f8:d13:f81:21c:14ff:fe01:12a3; Original-Received: from tjmaciei-mobl4.localnet (unknown [IPv6:2601:1c0:5803:81c9:40d2:14bc:2276:38b6]) by gondolin.macieira.info (Postfix) with ESMTPSA id E677211A7D6 for ; Fri, 21 Aug 2015 21:06:25 -0700 (PDT) User-Agent: KMail/4.14.9 (Linux/4.1.3-1-desktop; KDE/4.14.9; x86_64; ; ) In-Reply-To: X-Original-Sender: thiago@macieira.org X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of thiago@macieira.org designates 2a01:4f8:d13:f81:21c:14ff:fe01:12a3 as permitted sender) smtp.mailfrom=thiago@macieira.org 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:19958 Archived-At: On Friday 21 August 2015 19:42:13 NDos Dannyu wrote: > 2015=EB=85=84 8=EC=9B=94 22=EC=9D=BC =ED=86=A0=EC=9A=94=EC=9D=BC =EC=98= =A4=EC=A0=84 11=EC=8B=9C 24=EB=B6=84 55=EC=B4=88 UTC+9, Thiago Macieira =EB= =8B=98=EC=9D=98 =EB=A7=90: > > You're saying that the function doit above should return null if it was > > called > > with a reference to a temporary. But if it does so, how will it print t= he > > value that was referenced? >=20 > Does printf need its address?? No. The point is that the function "doit" needs to know how to obtain the= =20 value, regardless of whether it's a reference to a temporary or a reference= to=20 something more permanent. > > Besides, we're missing an important aspect: why do you want this? What'= s > > the > > motivation? >=20 > I'm writing my story again: >=20 > I have a value class indicating a finite discrete random variable. > But I had a problem. For example, assume that I have a variable named X. > But how can P(X Things will get much more complicated if I have multiple variables, X, Y > and Z, > and I have to do like P(X|Z|) or something. What's is P and what is squaring the variable here? How should I interpret = the=20 equal sign above? > So I decided to make a bind of variables. > It would be a tree structure, consisting of other binds or variables. > If it consists of references of variables, it will know what variables ar= e > same(or dependant) and what variables are different(or indepentant). > But how can I deal with rvalues? For examples, 1 can be seen as a variabl= e > which is always 1. Correct. > But it has no name. It is just 1. It is always indepentant from > other variables. Right. It may also be different from other 1s. > So I made it to consist of const lvalue references, > which can initialized with lvalue or rvalue. > But how can I determine it refers to lvalue or rvalue?? I couldn't find a= ny > solution from the standard library. You cannot. --=20 Thiago Macieira - thiago (AT) macieira.info - thiago (AT) kde.org Software Architect - Intel Open Source Technology Center PGP/GPG: 0x6EF45358; fingerprint: E067 918B B660 DBD1 105C 966C 33F5 F005 6EF4 5358 --=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/. .