# uses the Decorator module on my blog post
# I'm also using ActiveSupport's Inflector to save time, but you get the idea
require 'active_support'

class Symbol
  def to_class
    Kernel.const_get(Inflector::camelize(self))
  end
end

class Whip
  include Decorator
end

class Milk
  include Decorator
end

class Sprinkles
  include Decorator
end

class Coffee
  def self.with(*extras)
    extras.inject(self.new) { |drink, extra| drink = extra.to_class.new(drink) }
  end
end

# simple coffee
Coffee.new

# coffee with milk, whip and sprinkles
Coffee.with :milk, :whip, :sprinkles