Fix for http://brandonhilkert.com/blog/ruby-gem-configuration-patterns/

megalotto.rb

module MegaLotto
  class Configuration
    attr_accessor :drawing_count

    def initialize
      @drawing_count = 6
    end
  end

  class Drawing
    attr_accessor :config

    def initialize(config = MegaLotto.configuration)
      @config = config
    end

    def draw
      config.drawing_count.times.map { single_draw }
    end

    private

    def single_draw
      rand(0...60)
    end
  end

  class << self
    attr_writer :configuration
  end

  def self.configuration
    @configuration ||= Configuration.new
  end

  def self.reset
    @configuration = Configuration.new
  end

  def self.configure
    yield(configuration)
  end
end

MegaLotto.configure do |config|
  config.drawing_count = 10
end

puts MegaLotto::Drawing.new.draw