220 30687 article Path: news.gmane.org!.POSTED!not-for-mail From: schreiber.corentin@gmail.com Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Has applying a template to multiple statements been considered? 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Sun, 29 Jan 2017 03:01:23 -0800 (PST) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.157.27.211 with SMTP id v19ls4660770otv.18.gmail; Sun, 29 Jan 2017 03:01:22 -0800 (PST) X-Received: by 10.157.16.48 with SMTP id h45mr1285044ote.10.1485687682286; Sun, 29 Jan 2017 03:01:22 -0800 (PST) In-Reply-To: <26585b82-6c88-4ae5-b90b-c3643fa9f6cb@isocpp.org> X-Original-Sender: schreiber.corentin@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:30687 Archived-At: ------=_Part_984_194142502.1485687681748 Content-Type: multipart/alternative; boundary="----=_Part_985_218977819.1485687681748" ------=_Part_985_218977819.1485687681748 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Le samedi 28 janvier 2017 09:26:29 UTC+1, eya...@tx.technion.ac.il a =C3=A9= crit : > > (I've moved this question from=20 > http://stackoverflow.com/questions/41904201/ as per suggestions there.) > > In C++, we currently have to template function and variable definitions= =20 > individually: > > template void foo() { /* ... */ } > template void bar() { /* ... */ } > template std::vector baz; > > well, I would expect the template keyword to be able to apply to braced= =20 > scopse, similarly to namespaces, so that I could write: > > template { > void foo() { /* ... */ } > void bar() { /* ... */ } > std::vector baz; > } > > or at least > > template { > void foo() { /* ... */ } > void bar() { /* ... */ } > std::vector baz; > } > > I'm pretty sure somebody has already proposed this - am I right? If so,= =20 > can someone give me a link to the discussion and/or the decision? GIve a= =20 > brief explanation of why this was rejected? > > It seems to me (correct me if I'm wrong) that this should not interfere= =20 > with existing syntax not make the compiler have to work harder. > > This seems like a templated namespace. Some pointers on that: https://groups.google.com/a/isocpp.org/forum/#!searchin/std-proposals/templ= ate$20namespace/std-proposals/8IDbb1L5_UA/MqmIYyYHVUcJ https://groups.google.com/a/isocpp.org/forum/#!searchin/std-proposals/templ= ate$20namespace/std-proposals/ficfBQIgR4c/FRPjJ1QFcjoJ https://groups.google.com/a/isocpp.org/forum/#!search/cschreib/std-proposal= s/-3Q3C5FPuPE/L7yaWHAJwmsJ It seems the idea (which I like) has not generated much enthusiasm so far.= =20 I suppose this is because you can mostly achieve the same result by using a= =20 templated structure: template struct somestruct { static void foo() { /* ... */ } static void bar() { /* ... */ } static std::vector baz; }; The only difference is that you have to prefix all your calls by=20 "somestruct::", and add "static" to all the declarations. Not the=20 prettiest, but it works. --=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/cc8aaf35-d848-477e-b185-ffa260df0265%40isocpp.or= g. ------=_Part_985_218977819.1485687681748 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
Le samedi 28 janvier 2017 09:26:29 UTC+1, eya...@tx.techni= on.ac.il a =C3=A9crit=C2=A0:
(I've moved this question from http://stackoverflow.com/questions/419042= 01/ as per suggestions there.)

In C++, we currently have to temp= late function and variable definitions individually:

template <typename T> void foo() <= span style=3D"color:#660">{ /* ... */ }
template <typename T> void bar() {<= span style=3D"color:#000"> /* ... */ }
template <= typename T> std::vector<T> baz;

well, I would expect the template keyword to be ab= le to apply to braced scopse, similarly to namespaces, so that I could writ= e:

template <typename T> {
void foo() { /* ... */ }
void bar() { /* ... */ }
std::vector<T> baz;
}

or at least

tem= plate &= lt;typename T> {void <= /code>foo<T>() { /* ... */ }<= br>void<= /span> = bar<T= >() { /* ... */ }
std::vector<T> baz;
}

I'm pretty sure somebody has alr= eady proposed this - am I right? If so, can someone give me a link to the d= iscussion and/or the decision? GIve a brief explanation of why this was rej= ected?

It seems to me (correct me if I'm wrong) that this should= not interfere with existing syntax not make the compiler have to work hard= er.


This seems like a templated namespac= e. Some pointers on that:
https://groups.google.com/a/isocpp.org/forum/#= !searchin/std-proposals/template$20namespace/std-proposals/8IDbb1L5_UA/MqmI= YyYHVUcJ
https://groups.google.com/a/isocpp.org/forum/#!searchin/std-pro= posals/template$20namespace/std-proposals/ficfBQIgR4c/FRPjJ1QFcjoJ
https= ://groups.google.com/a/isocpp.org/forum/#!search/cschreib/std-proposals/-3Q= 3C5FPuPE/L7yaWHAJwmsJ

It seems the idea (which I like) has not gener= ated much enthusiasm so far. I suppose this is because you can mostly achie= ve the same result by using a templated structure:
template <typename T>
struct somestruct {
=C2=A0 static <= /span>void= foo() { /* ... */ }=C2=A0 s= tatic void bar() { /* ... */ }
= =C2=A0 sta= tic std::vector<T> baz;
};

The only difference is that you have to = prefix all your calls by "somestruct::", and add "static&qu= ot; to all the declarations. Not the prettiest, but it works.

--
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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/cc8aaf35-d848-477e-b185-ffa260df0265= %40isocpp.org.
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