220 10477 article Path: news.gmane.org!not-for-mail From: Tony V E Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Researching any-like general type erasure (not a proposal as of now). Date: Thu, 1 May 2014 16:54:55 -0400 Lines: 111 Approved: news@gmane.org Message-ID: References: <3c02d482-360c-40fc-973c-7a348566d2ff@isocpp.org> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: multipart/alternative; boundary=001a11c22568969f5304f85ce0ee X-Trace: ger.gmane.org 1398977702 30356 80.91.229.3 (1 May 2014 20:55:02 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Thu, 1 May 2014 20:55:02 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBCUZ5QWKNQIKB2MKTMCRUBBR6QZDQ@isocpp.org Thu May 01 22:54:58 2014 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-wi0-f198.google.com ([209.85.212.198]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1Wfy0P-000459-DQ for gclcip-std-proposals@m.gmane.org; Thu, 01 May 2014 22:54:57 +0200 Original-Received: by mail-wi0-f198.google.com with SMTP id cc10sf564407wib.5 for ; Thu, 01 May 2014 13:54:57 -0700 (PDT) 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=Gjkp9WTv+rQ5tKxeXGQj8+LXbMbTdfWeQakD0zVNdGs=; b=fbNz44jnHzykz4GZg0+BBRWh3mIVMrWHVFNOxt4EcIGDsz7p2x82CO3klD51B0WSND HQdYv9ZRGGwlvwWyoalWoWyyZzxw5Yn/IS/hss6qmI4ErmVYArHO/Nhz8qFvbHbuZyDn xd0GgqyOBD5gXrcOqlX7wyzco2EWX/IzmhShlJvp84/TWnJFrv7hBeiTpYdlTZ8/tsKu c8uLtMvHgqmlDm3v+XVoPqV3LV6irWfaEQA1xvYcYG89epFrFog647dPsISf+XC7Cmxg iFJ1ezr6d/9NI0oCTEXlCBLV6JNQOiVkbJi5uL4vAcDC7NjxeyzLpA2/Se5HKdf8/rb8 n4aw== X-Gm-Message-State: ALoCoQldOtA6x/gkuk4tP+W0ewOwb1nzx2SOR94DN6JemjqdgxYsCDQ6jKkXGYb7M/Wb/dReEej7 X-Received: by 10.180.76.143 with SMTP id k15mr445102wiw.6.1398977697033; Thu, 01 May 2014 13:54:57 -0700 (PDT) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.152.6.6 with SMTP id w6ls202750law.2.gmail; Thu, 01 May 2014 13:54:55 -0700 (PDT) X-Received: by 10.152.1.8 with SMTP id 8mr9046467lai.1.1398977695822; Thu, 01 May 2014 13:54:55 -0700 (PDT) Original-Received: from mail-lb0-x230.google.com (mail-lb0-x230.google.com [2a00:1450:4010:c04::230]) by mx.google.com with ESMTPS id q5si12109186lah.122.2014.05.01.13.54.55 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Thu, 01 May 2014 13:54:55 -0700 (PDT) Received-SPF: pass (google.com: domain of tvaneerd@gmail.com designates 2a00:1450:4010:c04::230 as permitted sender) client-ip=2a00:1450:4010:c04::230; Original-Received: by mail-lb0-f176.google.com with SMTP id w7so2484928lbi.35 for ; Thu, 01 May 2014 13:54:55 -0700 (PDT) X-Received: by 10.152.43.135 with SMTP id w7mr3584586lal.32.1398977695487; Thu, 01 May 2014 13:54:55 -0700 (PDT) Original-Received: by 10.112.136.165 with HTTP; Thu, 1 May 2014 13:54:55 -0700 (PDT) In-Reply-To: <3c02d482-360c-40fc-973c-7a348566d2ff@isocpp.org> X-Original-Sender: tvaneerd@gmail.com X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of tvaneerd@gmail.com designates 2a00:1450:4010:c04::230 as permitted sender) smtp.mail=tvaneerd@gmail.com; dkim=pass header.i=@gmail.com; dmarc=pass (p=NONE dis=NONE) header.from=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:10477 Archived-At: --001a11c22568969f5304f85ce0ee Content-Type: text/plain; charset=UTF-8 On Thu, May 1, 2014 at 2:04 PM, wrote: > Hello everyone, > > There is a thing I am really interested in that I think would be of > general interest for the c++ community. > I would like to generate some discussion on the topic. The intention of > this post is to collect ideas > and prior art to any-type like erasure. > > So far we have library versions of any-type like erasure, but none of them > is perfect. For reference > on the available solutions I will leave here the excellent blog entries > from Andrzej: > > http://akrzemi1.wordpress.com/2013/11/18/type-erasure-part-i/ > http://akrzemi1.wordpress.com/2013/12/06/type-erasure-part-ii/ > http://akrzemi1.wordpress.com/2013/12/11/type-erasure-part-iii/ > http://akrzemi1.wordpress.com/2014/01/13/type-erasure-part-iv/ > > What I wonder is how we could approach a perfect solution to have this > into the language avoiding the > boiler-plate. > > For now I can think of several solutions: > > 1. Build type erasure directly into the language. This would require > maybe, and would be related also > to overloading operator. (which currently cannot be done). Overloading > this operator could enable > classes like copy_on_write and optional to have the same interface > as the original class, > but this goes beyond the intention of this research. > https://github.com/boostcon/cppnow_presentations_2013/blob/master/thu/overloading_dot.pdf?raw=true -- --- 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/. --001a11c22568969f5304f85ce0ee Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable



On Thu, May 1, 2014 at 2:04 PM, <germandiago@gmail.com>= ; wrote:
Hello ev= eryone,

There is a thing I am really interested in that = I think would be of general interest for the c++ community.
I would like to generate some discussion on the topic. The intention o= f this post is to collect ideas
and prior art to any-type like er= asure.

So far we have library versions of any-type= like erasure, but none of them is perfect. For reference
on the available solutions I will leave here the excellent blog entrie= s from Andrzej:

=C2=A0 =C2=A0=C2=A0http://akrzemi1.wordpress.com/2013/12/11/type-erasure-part= -iii/
=C2=A0 =C2=A0 =C2=A0
= What I wonder is how we could approach a perfect solution to have this into= the language avoiding the=C2=A0
boiler-plate.

For now I can think of several = solutions:

1. Build type erasure directly into the= language. This would require maybe, and would be related also
to overloading operator. (which currently cannot be done). Overloading this= operator could enable
classes like copy_on_write<T> and op= tional<T> to have the same interface as the original class,
but this goes beyond the intention of this research.

--

---
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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>.
--001a11c22568969f5304f85ce0ee-- .