This is a Ruby tree! It shows every object from the Ruby Programming Language in a tree format.
# Symbol.upcase (from ruby core) --- upcase(*options) -> symbol --- Equivalent to `sym.to_s.upcase.to_sym`. See String#upcase.
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.