Specifying C++ symbols in C++ namespaces

[Jacob Carlborg]

On 03/04/14 00:07, Walter Bright wrote:
> Here's Andrei's proposal:
>
>      extern (C++) template nspace() {
>          int foo();
>      }
>
> It would be accessed in D by:
>
>     nspace!().foo();
>
> A possible enhancement would be to allow (for all templates with no
> parameters):
>
>      nspace.foo();
>
> Note that:
>
>      template nspace() {
>          extern (C++) int foo();
>      }
>
> would not put foo() in a C++ namespace, although it would still be
> accessed from D as:
>
>      nspace.foo();
>
> One downside of this proposal is that if we ever (perish the thought!)
> attempted to interface to C++ templates, this design would preclude that.

I like using a UDA or pragma better:

@namespace("nspace")
{
     extern (C++) int foo ();
}

Or

pragma(cpp_namespace, "nspace")
{
     extern (C++) int foo ();
}

Then it's also possible to use this syntax:

@namespace("nspace"):

extern (C++) int foo ();

The only advantage I can see with using "template" is that templates can 
be mixed in, it would be similar to the using declarative in C++.

-- 
/Jacob Carlborg