Playing with class methods and such

coffee.rb

#!/usr/bin/env ruby

class Milk
        def self.cost
                puts "  with Milk"
                0.2
        end
end

class Sugar
        def self.cost
                puts "  with Sugar"
                0.3
        end
end

class Cream
        def self.cost
                puts "  with Cream"
                0.1
        end
end

class Coffee
        attr :cost, true

        def initialize
                @cost = 2
        end

        def self.with( *args )
                coffee_obj = Coffee.new
                puts "Creating coffee.. "
                args.each do |field|
                        case field
                        when :milk
                                coffee_obj.cost += Milk.cost
                        when :sugar
                                coffee_obj.cost += Sugar.cost
                        when :cream
                                coffee_obj.cost += Cream.cost
                        end

                end
                return coffee_obj

        end
end

drink = Coffee.with :milk, :cream, :sugar

print "Cost of coffee: #{drink.cost}\n"