220 34240 <635c6793-0bb8-4407-b890-04ab33d1fe8b@isocpp.org> article Path: news.gmane.org!.POSTED!not-for-mail From: Bastien Penavayre 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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Looking forward to hearing additional feedback= =20 > from others, I hope it moves forward. > Thanks. > Simple syntax question: why not placing constexpr() next to where=20 > 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= =20 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=20 specifier for lambdas and syntactically I'm only expending it, i'm not=20 creating something new. auto func() constexpr; //invalid now | This alternative seems more consistent, even with lambda functions=20 examples. You can notice that it's the case with the lambdas in my exemple and I=20 agree, but for now lambdas and functions/methods don't have the same syntax to=20 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"= =20 I feel like it's not a bad idea to put it at the front of the function, to= =20 make it more visible. I hope I've answered your question correctly. If you have any other, please, feel free to ask. --=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/635c6793-0bb8-4407-b890-04ab33d1fe8b%40isocpp.or= g. ------=_Part_950_1368746726.1504215147233 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Le jeudi 31 ao=C3=BBt 2017 22:17:41 UTC+2, Ricardo Andrade= a =C3=A9crit=C2=A0:
Very interesting proposal. Looking forward to hearing additional f= eedback from others, I hope it moves forward.
Thanks= ..
S= imple 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 m= y motivation was the following:

To make as little = change as possible to the existing grammar.
As of now constexpr is a fro= nt specifier for function/members, tail specifier for lambdas and syntactic= ally I'm only expending it, i'm not creating something new.
auto func() constexpr; //invalid now

=C2=A0| 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 n= ow 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 orient= ed front, as constexpr would allow "specialization" I feel like i= t's not a bad idea to put it at the front of the function, to make it m= ore visible.

I hope I've answered your questio= n correctly.
If you have any other, please, feel free to ask.

--
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.
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.
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