220 12889 article Path: news.gmane.org!not-for-mail From: Myriachan Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: unevaluated this Date: Mon, 15 Sep 2014 11:32:54 -0700 (PDT) Lines: 102 Approved: news@gmane.org Message-ID: References: <009e6218-1e2b-402d-ab1a-e8ebf29f8f77@isocpp.org> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_Part_2211_985551478.1410805974216" X-Trace: ger.gmane.org 1410805987 16772 80.91.229.3 (15 Sep 2014 18:33:07 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Mon, 15 Sep 2014 18:33:07 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBDKLT4PURQHRBWPB3SQAKGQE7TC7FCY@isocpp.org Mon Sep 15 20:33:03 2014 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-qc0-f198.google.com ([209.85.216.198]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1XTb5A-0002cX-1o for gclcip-std-proposals@m.gmane.org; Mon, 15 Sep 2014 20:33:00 +0200 Original-Received: by mail-qc0-f198.google.com with SMTP id r5sf13409202qcx.9 for ; Mon, 15 Sep 2014 11:32:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=date:from:to:message-id:in-reply-to:references:subject:mime-version :x-original-sender:reply-to:precedence:mailing-list:list-id :list-post:list-help:list-archive:list-subscribe:list-unsubscribe :content-type; bh=3PC1Y5EHMV5f7Tqcn/p2iz+KsnFtLfgHftN8fP0Qvds=; b=jllmz7H/m9A/XrHjZ3lnPf3CjsRmcU1WA/sea1TcGLuFJJLgxxdcFAVZcBImH3F1NL 060UY8TuIyj+jW+A7NgOBj961gBY0ND/BFUZSW+jSaOYtAXFEbJOB369jX9A4bUW9HhF p//SOztkMoNSeLh6NaB2v6tUdHKylUquffeskmk966z7KLYnOWDPZFkMKtGNsoI29zZm zFkeWJho0FcE9kNWbXX8NzHRkF7oPctW/lKm/UjcsIjvE7kMpnyuSfzd02qb6sbpK5bL +fghdaMGEuFmzvB/V/hrx5NK4eONWbDzb1v7ITiD6NM8BvaksludiMQ9XmtxVqz1JP8i tbUA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:date:from:to:message-id:in-reply-to:references :subject:mime-version:x-original-sender:reply-to:precedence :mailing-list:list-id:list-post:list-help:list-archive :list-subscribe:list-unsubscribe:content-type; bh=3PC1Y5EHMV5f7Tqcn/p2iz+KsnFtLfgHftN8fP0Qvds=; b=X4dZ4ISUhB7zdbArjU1nu86eLgg5grbL/b+CfJ5r8DOCQElWOIaPO7D9OBHKYkEh5E SkVPR0mnutHnbyZmGuuRAXSJB6LJG3uyr/nds22rLZNIxZ9m3aGYDPxSBdCukvfJ1GlI gZ7Gniz+G6Z/qs3pxBmv0H7D3Z3SoKofuHgn/9VmXEY/qVOnACKvfM9zbQjlIYUiBKwu zsn5gQeJ1UuKdNs4zAK2Vs0uff5dcYdALUnVEHuS4pNJ+pNS6eLIhuYcYQTbg+yqyQXZ hnJTzQZyXNuqDBTT/jKcjWs31ctHiGuMoKlHgJ7rxn2nphdwzKYrSy7U3cD9xUyTcmCQ Y0gg== X-Gm-Message-State: ALoCoQm8deEaJNQRB/orKc5XGEMBJUjcaz+CKeILxbQkB6SmnwzIFNhLKQIVzt3buQyRleAdkoiL X-Received: by 10.52.36.197 with SMTP id s5mr16275745vdj.5.1410805978048; Mon, 15 Sep 2014 11:32:58 -0700 (PDT) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.50.43.225 with SMTP id z1ls2159410igl.30.canary; Mon, 15 Sep 2014 11:32:57 -0700 (PDT) X-Received: by 10.50.114.98 with SMTP id jf2mr247525igb.4.1410805977048; Mon, 15 Sep 2014 11:32:57 -0700 (PDT) In-Reply-To: <009e6218-1e2b-402d-ab1a-e8ebf29f8f77@isocpp.org> X-Original-Sender: myriachan@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:12889 Archived-At: ------=_Part_2211_985551478.1410805974216 Content-Type: text/plain; charset=UTF-8 On Monday, September 15, 2014 9:17:17 AM UTC-7, Sean Middleditch wrote: > > Another proposal carrying on from work I did earlier. This is a > continuation of the decltype(class) feature I suggested some time back but > with Ville's suggestion taken to heart. It's now a proposal for allowing > `this` in unevaluated contexts (decltype, sizeof, etc.) anywhere in a class > definition body or base specifier list as well as a convenient helper > `std::this_t`. > > > http://htmlpreview.github.io/?https://github.com/seanmiddleditch/CPlusPlus/blob/master/unevaluated-this.html > > Thoughts/comments/critiques would be appreciated. Thanks! > I don't see how std::this_t could be implemented, because there's no way it could know in which context it's being used. Other than the amount of typing, this would work fine if this is allowed throughout class scope in all unevaluated contexts: using my_type = std::remove_cv_t>; Melissa -- --- 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. Visit this group at http://groups.google.com/a/isocpp.org/group/std-proposals/. ------=_Part_2211_985551478.1410805974216 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
On Monday, September 15, 2014 9:17:17 AM UTC-7, Sean Middl= editch wrote:
= Another proposal carrying on from work I did earlier. This is a continuatio= n of the decltype(class) feature I suggested some time back but with Ville'= s suggestion taken to heart. It's now a proposal for allowing `this` in une= valuated contexts (decltype, sizeof, etc.) anywhere in a class definition b= ody or base specifier list as well as a convenient helper `std::this_t`.

Thoughts/comments/critiques would be app= reciated. Thanks!

I don't see how std::thi= s_t could be implemented, because there's no way it could know in which con= text it's being used.  Other than the amount of typing, this would wor= k fine if this i= s allowed throughout class scope in all unevaluated contexts:

<= span style=3D"color: #008;" class=3D"styled-by-prettify">using my_type =3D std::remove_cv_t<std::remove_reference_t<decltype(*this)>= ;>;
=

Melissa

--

---
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.
Visit this group at http://groups.google.com/a/isocpp.org/group/std-proposals/<= /a>.
------=_Part_2211_985551478.1410805974216-- .