This is a Ruby tree! It shows every object from the Ruby Programming Language in a tree format.
# Gem::Specification.extensions (from ruby core) ### Implementation from Specification --- extensions() --- Extensions to build when installing the gem, specifically the paths to extconf.rb-style files used to compile extensions. These files will be run when the gem is installed, causing the C (or whatever) code to be compiled on the user’s machine. Usage: spec.extensions << 'ext/rmagic/extconf.rb' See Gem::Ext::Builder for information about writing extensions for gems.
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.