Re: String literal as template parameter?

From:

Alberto Ganesh Barbati <AlbertoBarbati@libero.it>

Newsgroups:

comp.lang.c++.moderated

Date:

Mon, 14 Apr 2008 21:24:25 CST

Message-ID:

<xpQMj.58173$FR.253057@twister1.libero.it>

mark.zaytsev@gmail.com ha scritto:

On Apr 14, 12:43 pm, Sean Hunt <ride...@gmail.com> wrote:

I find his extension proposal to allow a string-literal
as an alternative argument of variadic non-type templates
(of character type) quite interesting. This is IMO the
first approach, where I would see any chance of acceptance
on implementors side.

Yeah. This is a good idea. It doesn't take a lot of wording either:

Sean Hunt

It is also desirable to have a way to reconstruct string literal from
variadic non-type template of character type. maybe like:

template < char ... s >
const char* a = { s };

The draft already provides a syntax for that, it is:

   template <char... s>
   class S
   {
      const char a[sizeof...(s)];
   };

   template <char... s>
   const char S<s>::a[sizeof...(s)] = { s... };

In another post of mine I proposed to leave out the final '\0' from the
char sequence. In that case we would have to add it, like this:

   template <char... s>
   class S
   {
      const char a[sizeof...(s) + 1];
   };

   template <char... s>
   const char S<s>::a[sizeof...(s) + 1] = { s..., '\0' };

not a big deal.

Ganesh

--
      [ See http://www.gotw.ca/resources/clcm.htm for info about ]
      [ comp.lang.c++.moderated. First time posters: Do this! ]