220 34242 article Path: news.gmane.org!.POSTED!not-for-mail From: Ricardo Fabiano de Andrade Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: constexpr only functions: arbitrary literal types for non-type, constexpr arguments, is_constexpr... 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[209.85.220.41]) by mx.google.com with SMTPS id y14sor55612iof.18.2017.08.31.15.22.50 for (Google Transport Security); Thu, 31 Aug 2017 15:22:50 -0700 (PDT) Received-SPF: pass (google.com: domain of ricardofabianodeandrade@gmail.com designates 209.85.220.41 as permitted sender) client-ip=209.85.220.41; X-Received: by 10.107.32.14 with SMTP id g14mr6763472iog.147.1504218169762; Thu, 31 Aug 2017 15:22:49 -0700 (PDT) Original-Received: by 10.107.13.14 with HTTP; Thu, 31 Aug 2017 15:22:49 -0700 (PDT) In-Reply-To: <635c6793-0bb8-4407-b890-04ab33d1fe8b@isocpp.org> X-Original-Sender: ricardofabianodeandrade@gmail.com X-Original-Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=a/72S/Lc; spf=pass (google.com: domain of ricardofabianodeandrade@gmail.com designates 209.85.220.41 as permitted sender) smtp.mailfrom=ricardofabianodeandrade@gmail.com; dmarc=pass (p=NONE sp=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:34242 Archived-At: --001a1140c1d6ac68370558141507 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Thu, Aug 31, 2017 at 4:32 PM, Bastien Penavayre wrote= : > Le jeudi 31 ao=C3=BBt 2017 22:17:41 UTC+2, Ricardo Andrade a =C3=A9crit : >> >> Very interesting proposal. Looking forward to hearing additional feedbac= k >> from others, I hope it moves forward. >> > Thanks. > >> Simple syntax question: why not placing constexpr() next to where >> noexcept() is, at the end of the function declaration/definition? >> > That's a good question. I'm not opposed to the idea but my motivation was > the following: > > To make as little change as possible to the existing grammar. > As of now constexpr is a front specifier for function/members, tail > specifier for lambdas and syntactically I'm only expending it, i'm not > creating something new. > auto func() constexpr; //invalid now > > | This alternative seems more consistent, even with lambda functions > examples. > You can notice that it's the case with the lambdas in my exemple and I > agree, > but for now lambdas and functions/methods don't have the same syntax to > express their constexpr-ness. > A Proposal to correct this wouldn't be affected by this proposal. > > On a more design oriented front, as constexpr would allow "specialization= " > I feel like it's not a bad idea to put it at the front of the function, t= o > make it more visible. > > I hope I've answered your question correctly. > If you have any other, please, feel free to ask. > I was interested in the motivation behind your choice and after the explanation I am more open to it. I'll be following the thread. > -- > 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/635c6793-0bb8-4407- > b890-04ab33d1fe8b%40isocpp.org > > . > --=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. To view this discussion on the web visit https://groups.google.com/a/isocpp= ..org/d/msgid/std-proposals/CA%2BfGSbMS_aR8n6MSaRHNYh6vO%2BWxtb4KiKnWs9t2Avr= E9otE%3Dw%40mail.gmail.com. --001a1140c1d6ac68370558141507 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
On Thu, Aug 31, 2017 at 4:32 PM, Bastien Penavayre <s= wac31@gmail.com> wrote:
Le jeudi 31 ao=C3=BBt 2017 22:17:41 UTC+2, Ricardo A= ndrade a =C3=A9crit=C2=A0:
Very interesting proposal. Looking forward to hearing add= itional feedback from others, I hope it moves forward.
Thanks.
Simple syntax question: why not placing constexpr() next to w= here noexcept() is, at the end of the function declaration/definition?
That's a good question. I'm not opposed to= the idea but my motivation was the following:

To = make as little change as possible to the existing grammar.
As of now con= stexpr is a front specifier for function/members, tail specifier for lambda= s and syntactically I'm only expending it, i'm not creating somethi= ng new.
auto func() constexpr; //invalid now
=C2=A0| This alternative seems more consistent, even wi= th lambda functions examples.
You can notice that it's the ca= se with the lambdas in my exemple and I agree,
but for now lambda= s and functions/methods don't have the same syntax to express their con= stexpr-ness.
A Proposal to correct this wouldn't be affected = by this proposal.

On a more design oriented front,= as constexpr would allow "specialization" I feel like it's n= ot a bad idea to put it at the front of the function, to make it more visib= le.

I hope I've answered your question correct= ly.
If you have any other, please, feel free to ask.
<= /blockquote>

I was interested in the motivation behind y= our choice and after the explanation I am more open to it.
I'= ll be following the thread.

--
You received this message because you are subscribed to the Google Groups &= quot;ISO C++ Standard - Future Proposals" group.
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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/635c= 6793-0bb8-4407-b890-04ab33d1fe8b%40isocpp.org.

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