Request Assistance Calling D from C++: weird visibility issue inside struct and namespace

[MGW]

On Wednesday, 8 November 2017 at 06:34:27 UTC, Andrew Edwards 
wrote:
> I'm having a little bit of problem calling D code from C++ and 
> would appreciate some assistance. First, given the following 
> C++ program wich compiles, links, and runs without any problem:

The useful material.
https://www.youtube.com/watch?v=HTgJaRRfLPk