This is updated version:

https://lh3.googleusercontent.com/-CwmrmMaIeqg/Upywjx1vdBI/AAAAAAAAAm0/2qZBmOZFL-0/s1530/Ruby.png

I think I should change something because of many red lines.

And I didn't understand about "- Similar for the blue arrows."  Module doesn't unclude self arrows. Is is correct on updated version?