220 4805 article Path: news.gmane.org!not-for-mail From: Mikhail Semenov Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Re: Changing lambda scope Date: Mon, 3 Jun 2013 08:56:57 +0100 Lines: 200 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: multipart/alternative; boundary=089e0118403e161dcd04de3b4f31 X-Trace: ger.gmane.org 1370246221 19200 80.91.229.3 (3 Jun 2013 07:57:01 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Mon, 3 Jun 2013 07:57:01 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBDC55PNFRYGRBS4YWGGQKGQETCY466A@isocpp.org Mon Jun 03 09:57:01 2013 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-ob0-f199.google.com ([209.85.214.199]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1UjPdV-0002P1-7Z for gclcip-std-proposals@m.gmane.org; Mon, 03 Jun 2013 09:57:01 +0200 Original-Received: by mail-ob0-f199.google.com with SMTP id xk17sf22907980obc.10 for ; Mon, 03 Jun 2013 00:57:00 -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; bh=Al9mZegqHXLMrnLLA8Eav2/3hjWLH/tjVB/cc+fM7+U=; b=RmywAikYr4KrtUd/6hs5vp31/a854BBrH+CIBUlD7gUaIPcqvllhKsvNw2vj58Ft2M 36e7AhdGmGAynCpdN8R5arFP66l8ZhRjG6rnNtU85YYwnzJM8zy1JC5oiI5zww6DRYr3 lOefPpUiX+Az/F1r4hvk6cO/XGqYRFyOIYkiyyhwTamhCVwzlp2rCpA8Y0Wq5y1lseGP UolrtxZP08DfzbHMJo4Pni0BNqSyEVcsyFyW7PGJjEYBEvzw+5vJLIxKVY92eHkDpy+u vXg28XuXCEoYZlEAw542RX7VUNJwxSpDnXpu7eC8MmNLWovsRlAd8Dz6wK4QXITPme/0 vzYg== X-Received: by 10.182.236.231 with SMTP id ux7mr5083429obc.5.1370246220209; Mon, 03 Jun 2013 00:57:00 -0700 (PDT) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.182.117.233 with SMTP id kh9ls182709obb.17.gmail; Mon, 03 Jun 2013 00:56:58 -0700 (PDT) X-Received: by 10.60.160.161 with SMTP id xl1mr7323417oeb.84.1370246218292; Mon, 03 Jun 2013 00:56:58 -0700 (PDT) Original-Received: from mail-ob0-x233.google.com (mail-ob0-x233.google.com [2607:f8b0:4003:c01::233]) by mx.google.com with ESMTPS id i7si13323894oef.53.2013.06.03.00.56.58 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Mon, 03 Jun 2013 00:56:58 -0700 (PDT) Received-SPF: pass (google.com: domain of mikhailsemenov1957@gmail.com designates 2607:f8b0:4003:c01::233 as permitted sender) client-ip=2607:f8b0:4003:c01::233; Original-Received: by mail-ob0-f179.google.com with SMTP id xk17so6608133obc.38 for ; Mon, 03 Jun 2013 00:56:58 -0700 (PDT) X-Received: by 10.60.83.73 with SMTP id o9mr3640577oey.137.1370246218127; Mon, 03 Jun 2013 00:56:58 -0700 (PDT) Original-Received: by 10.60.20.170 with HTTP; Mon, 3 Jun 2013 00:56:57 -0700 (PDT) In-Reply-To: X-Original-Sender: mikhailsemenov1957@gmail.com X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of mikhailsemenov1957@gmail.com designates 2607:f8b0:4003:c01::233 as permitted sender) smtp.mail=mikhailsemenov1957@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:4805 Archived-At: --089e0118403e161dcd04de3b4f31 Content-Type: text/plain; charset=ISO-8859-1 Richard, Have you tried to uncomment the return type? That might be the problem. Mikhail. On 2 June 2013 23:49, Richard Smith wrote: > On Sun, Jun 2, 2013 at 11:12 AM, Mikhail Semenov < > mikhailsemenov1957@gmail.com> wrote: > >> And the following code works. I think auto may be the problem. >>> >> #include >> #include >> bool ok = true; >> namespace range >> { >> template auto operator|(L l, R r) // -> int >> { >> return l(ok)+r(ok); >> } >> template auto map(T t) //-> std::function >> { >> return [=](bool range) -> int >> { >> if (range) return t.i; >> return 0; >> }; >> } >> } >> struct A >> { >> int i; >> A(int i1):i(i1) {} >> }; >> >> int main() >> { >> A a1(5); >> A a2(6); >> int k = >> range::map(a1) >> | range::map(a2); >> std::cout << k << std::endl; // 11 >> ok = false; >> >> k = >> range::map(a1) >> | range::map(a2); >> std::cout << k << std::endl; // 0 >> >> } >> > > This does not compile in Clang: > > :31:9: error: invalid operands to binary expression (' :12:16>' and ':12:16>') > | range::map(a2); > ^ ~~~~~~~~~~~~~~ > :37:9: error: invalid operands to binary expression (' :12:16>' and ':12:16>') > | range::map(a2); > ^ ~~~~~~~~~~~~~~ > > It appears that g++ includes the enclosing namespaces as associated > namespaces for local classes, contrary to the current rules in the standard. > > -- > > --- > 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/?hl=en. > > > -- --- 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/?hl=en. --089e0118403e161dcd04de3b4f31 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable
Richard,
=A0
Have you tried to uncomment the return type?
That might be the problem.
=A0
Mikhail.

On 2 June 2013 23:49, Richard Smith <richar= d@metafoo.co.uk> wrote:
On Sun, Jun 2, 2013 at 11:12 AM, Mikhail Semenov <mikhailsemenov1957@gmail.com> wrote:
And the following code works. I think auto may be the problem.
#include <iostream>
#inc= lude <functional>
bool ok =3D true;
namespace ra= nge
{
=A0=A0=A0 template<typename R, typename L> auto operator= |(L l, R r) // -> int
=A0=A0=A0 {
=A0=A0=A0=A0=A0=A0=A0=A0 return = l(ok)+r(ok);=A0=A0=A0=A0=A0=A0=A0
=A0=A0=A0 }
=A0=A0=A0 template<typename T> auto map(T t) //-&= gt; std::function<int(bool)>
=A0=A0=A0 {
=A0=A0=A0=A0=A0=A0=A0 return [=3D](bool range) -> in= t
=A0=A0=A0=A0=A0=A0=A0 {
=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0 if (range= ) return t.i;
=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0 return 0;
=A0=A0=A0= =A0=A0=A0=A0 };
=A0=A0=A0 }
}
struct A
{
=A0=A0 int i;=A0=A0 A(int i1):i(i1) {}
};

int main()
{=A0=A0=A0
=A0=A0=A0 A a1(5);
=A0=A0=A0 A a2(6);
=A0=A0=A0 int k =3D
=A0=A0=A0=A0=A0=A0=A0 range::map(a1)
=A0=A0=A0=A0=A0=A0=A0 | range::m= ap(a2);
=A0=A0=A0 std::cout << k << std::endl;=A0 // 11=A0= =A0=A0=A0=A0
=A0=A0=A0 ok =3D false;
=A0=A0=A0
=A0=A0=A0 k =3D=A0=A0=A0=A0=A0=A0=A0 range::map(a1)
=A0=A0=A0=A0=A0=A0=A0 | range::map(a2);
=A0=A0=A0 std::cout << k &= lt;< std::endl;=A0 // 0=A0=A0=A0=A0=A0
=A0=A0=A0
}
<= /blockquote>

This does not compile in Clang:

<stdin>:31:9: error: invalid operands to binary expression ('= ;<lambda at <stdin>:12:16>' and '<lambda at <stdi= n>:12:16>')
=A0 =A0 =A0 =A0 | range::map(a2);
=A0 =A0 =A0 =A0 ^ ~~~~~~~~~~~~~~
<stdin>:37:9: error: invalid operands to binary expression ('= ;<lambda at <stdin>:12:16>' and '<lambda at <stdi= n>:12:16>')
=A0 =A0 =A0 =A0 | range::map(a2);
=A0 =A0 =A0 =A0 ^ ~~~~~~~~~~~~~~

It appears that g++ includes the enclosing namespaces as associated na= mespaces for local classes, contrary to the current rules in the standard.<= /div>

--
=A0
---
You received this message because you are subs= cribed 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 a= t http://groups.google.com/a/isocpp.org/group/std-pr= oposals/?hl=3Den.
=A0
=A0

--
 
---
You received this message because you are subscribed to the Google Groups &= quot;ISO C++ Standard - Future Proposals" group.
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