Re: [boost] [parameter] - catching accidental duplicate parameters at compile time

From: Daniel Earwicker (daniel.earwicker_at_[hidden])
Date: 2005-11-07 07:57:13

On 11/3/05, David Abrahams <dave_at_[hidden]> wrote:
> Something like:
>
>   static char (& has_key(K const&) )[2];
>
>   BOOST_MPL_ASSERT_MSG(
>         sizeof(Next::has_key(make<K>())) == 1
>       , duplicate_keyword, (K)
>   );
>
> If you could submit a patch to the current CVS along with an
> expected-compilation-failure test case, I'd be happy to apply it.

Excellent, thanks.

One question about the above code: is make<> already declared somewhere?

In the meantime I've added this as a member of arg_list:

        template <class T>
        static const T &make();

Or how about passing has_key a pointer, as NULL pointers are easy to
make? Apologies for my ignorance about these details.

--Daniel.