Enumerate Constants in object space

object_sub_constants.rb

class Object
 def self.sub_constants(prefix = "", namespace=[])
   self.constants.each do |constant|
     constant = constant.to_s
     puts prefix + constant
     #puts eval("#{constant}.methods").inspect
     begin
       next if %w{ Object  Module  Class }.include?(constant) || namespace.include?(constant) 
       b = (namespace.dup) << constant
       eval_string = b.join('::')
       eval(eval_string).sub_constants(prefix + "     ", b)
     rescue
       next
     end
   end
 end
end

Object.sub_constants