You've seen Lance Bachmeier posting in the forums under the
bachmeier handle. He's put together a post for the D Blog showing
how to integrate R into a D program.
The Blog:
https://dlang.org/blog/2020/01/27/d-for-data-science-calling-r-from-d/
Reddit:
https://www.reddit.com/r/programming/comments/euobu1/d_for_data_science_calling_r_from_d/
It's also on Hacker News. If it isn't on the front page, just
search for "D for Data Science". Please don't post a direct link
if you find it on there, not until after it's been on there a few
days.
https://news.ycombinator.com/