gistfile1.rb

class Person
  def self.region(str, &blk)
    self.class_eval(&blk)
  end
end

class Joe < Person
  def name; "Joe"; end

  region "speaking" do
    def say_hi
      "Hi"
    end

    def say_hi_to(someone)
      return say_hi if someone.blank?
      "#{say_hi}, #{someone}"
    end
  end
end