This is a Ruby tree! It shows every object from the Ruby Programming Language in a tree format.
# Rake::Task.already_invoked (from gem rake-13.0.6) --- Has this task already been invoked? Already invoked tasks will be skipped unless you reenable them.
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.