This is a Ruby tree! It shows every object from the Ruby Programming Language in a tree format.
# DateTime.sec (from ruby core) --- d.sec -> fixnum d.second -> fixnum --- Returns the second (0-59). DateTime.new(2001,2,3,4,5,6).sec #=> 6
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.