First Draft: Symbol Representation (Export)

[Tim]

On Thursday, 29 February 2024 at 11:15:07 UTC, Richard (Rikki) 
Andrew Cattermole wrote:
> D's support for shared libraries has historically presented 
> challenges for users, especially when dealing with complex use 
> cases. This proposal aims to improve the user experience by 
> establishing a user story that will provide a consistent and 
> user-friendly approach to usage and compilation of binaries 
> without a thorough understanding of linkers.
>
> With the recent resolution of dmd's exportation support on 
> Windows (druntime support is still under development), we are 
> now ready to focus on making D's shared library capabilities 
> more accessible and usable for common use cases.
>
> Links: 
> [current](https://gist.githubusercontent.com/rikkimax/1d7cfdb8ed74e9e4efc9ba0208f42e7e/11e36e8a332324c5323792da2835337d0306a6c9) [latest](https://gist.github.com/rikkimax/1d7cfdb8ed74e9e4efc9ba0208f42e7e)

Can a module, which is compiled as part of the application, still 
contain prototypes for symbols from a DLL? Here is an example:
```D
extern(C++) void foo(const char *s, size_t length);
void foo(string s)
{
     foo(s.ptr, s.length);
}
```

Function `foo` is implemented in a C++ library, which could be 
compiled as a DLL. The module contains a prototype for the 
function, but also an overload with a more convenient interface 
for D. The module needs to be compiled, because it contains the 
overload. Can the prototype still be imported from a DLL and be 
part of the same module?