eigen_keyword.rb

class Object
  def eigen
    str = caller[0]
    /\w+(?=')/ =~ str
    singleton_class.send $&.to_sym
  end
end

class Animal
  def speak
    puts "An animal made noise"
  end
end

class Dog < Animal
  def speak
    puts "A dog spoke"
    eigen # calls speak in dog's singleton class's singleton class
    super # calls speak in Dog's superclass
  end
  class << self
    def speak
      puts "neat"
    end
  end
end

dog = Dog.new

class << dog # open up dog's singleton class
  def speak
    puts "#{self}: bowwow"
    super # calls speak in Dog class, the super of dog's singleton class
  end
  class << self # open up dog's singleton class's singleton class
    def speak
      puts "what?"
      super # calls speak in Dog's singleton class, the superclass of dog's singleton class's singleton class
    end
  end
end

dog.speak
# #<Dog:0x012b532>: bowwow
# A dog spoke
# what?
# neat
# An animal made noise
# => nil