This is a Ruby tree! It shows every object from the Ruby Programming Language in a tree format.
# Set.flatten! (from ruby core) --- flatten!() --- Equivalent to Set#flatten, but replaces the receiver with the result in place. Returns nil if no modifications were made.
This is MURDOC! A Ruby documentation browser inspired by Smalltalk-80. It allows you to learn about Ruby by browsing through its class hierarchies, and see any of its methods.