why do i need an extern(C): here?

[IGotD-]

On Thursday, 15 October 2020 at 21:29:59 UTC, WhatMeWorry wrote:
>
> I've go a small DLL and a test module both written in D. Why do 
> I need to use the extern(C)?  Shouldn't both sides be using D 
> name wrangling?
>

You have answered your own question. If you're not using 
extern(C), D just like C++ adds a lot of name mangling which is 
not "addSeven" but extra characters as well. GetProcAddress which 
is a Windows call has no idea about D name mangling and therefore 
will not find the function.