extern(Windows) behavior on non-Windows systems

[via Digitalmars-d]

On Wednesday, 11 June 2014 at 22:20:27 UTC, Walter Bright wrote:
> I've got an enhancement request to have it behave like 
> extern(C):
>
>     https://issues.dlang.org/show_bug.cgi?id=12894
>
> Thoughts? Anyone use extern(Windows) on non-Windows systems?

That example of "I want this calling convention on platform X and 
that other convention on platform Y" points to the deeper problem 
that (without a preprocessor) you can't do something like this in 
D:

     version(Windows)
         alias extern(Foo) = extern(Windows);
     else
         alias extern(Foo) = extern(C);

     extern(Foo):
         void foobar();
         int baz();

That reasoning also applies to various other attributes. IMO, 
repeating all of the declarations for the multiple variants you 
might want is not the right answer (DRY principle, etc.).