Is there any good reason why C++ namespaces are "closed" in D?

[Ali]

On Friday, 27 July 2018 at 23:15:44 UTC, Laeeth Isharc wrote:

> Because it's getting in the way of a decent prize - to be able 
> just to #include CPP headers and link with C++.

Just wanted to +1000000 on this one
Having this feature, and if marketed well, can be huge for D

This is 10 times a bigger deal than any other thing working for D 
right now