220 29392 article Path: news.gmane.org!.POSTED!not-for-mail From: Shi Yan Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: why not formally support meta programming. 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[2a00:1450:400c:c09::241]) by mx.google.com with ESMTPS id qp4si2555593wjb.30.2016.11.09.17.32.25 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 09 Nov 2016 17:32:25 -0800 (PST) Received-SPF: pass (google.com: domain of billconan@gmail.com designates 2a00:1450:400c:c09::241 as permitted sender) client-ip=2a00:1450:400c:c09::241; Original-Received: by mail-wm0-x241.google.com with SMTP id c17so200853wmc.3 for ; Wed, 09 Nov 2016 17:32:25 -0800 (PST) X-Received: by 10.28.125.3 with SMTP id y3mr3412827wmc.30.1478741545459; Wed, 09 Nov 2016 17:32:25 -0800 (PST) Original-Received: by 10.28.72.193 with HTTP; Wed, 9 Nov 2016 17:32:24 -0800 (PST) In-Reply-To: <7d99e4bd-5ae1-4615-96dd-c8849487c007@isocpp.org> X-Original-Sender: billconan@gmail.com X-Original-Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com; spf=pass (google.com: domain of billconan@gmail.com designates 2a00:1450:400c:c09::241 as permitted sender) smtp.mailfrom=billconan@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:29392 Archived-At: --001a11418c708825f00540e85845 Content-Type: text/plain; charset=UTF-8 I have tested on this page http://melpon.org/wandbox that this feature is available with gcc 7 and clang 4. I couldn't find how to obtain gcc 7 source code. I will see if I could build clang 4 On Wed, Nov 9, 2016 at 5:11 PM, wrote: > Thank you, this is indeed a cleaner solution. > > but is if constexpr available with any compiler today? event prerelease > compiler, I'd like to try. > > On Wednesday, November 9, 2016 at 4:45:17 PM UTC-8, Nicol Bolas wrote: >> >> A combination of `if constexpr` and template specialization can handle >> what you're doing: >> >> -- 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. To view this discussion on the web visit https://groups.google.com/a/isocpp.org/d/msgid/std-proposals/CAKO7S%3DKBacA_3p3z-payS4df2xe3HoYNekqg0wu0fXSjzwsTOw%40mail.gmail.com. --001a11418c708825f00540e85845 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
I have tested on this page=C2=A0http://melpon.org/wandbox

that this feat= ure is available with gcc 7 and clang 4.

I couldn&= #39;t find how to obtain gcc 7 source code.

I will= see if I could build clang 4

On Wed, Nov 9, 2016 at 5:11 PM, = <billconan@gmai= l.com> wrote:
Thank you, this is indeed a cleaner solution.

but is= if constexpr available with any compiler today? event prerelease compiler,= I'd like to try.

On Wednesday, November 9, 201= 6 at 4:45:17 PM UTC-8, Nicol Bolas wrote:
A combination of `if constexpr` and template special= ization can handle what you're doing:


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