Ruby factory example

factory.rb

class Driver
  class << self
    
    def list
      @list ||= {}
    end
    
    def add_subclass(subclass_name, subclass)
      list.store subclass_name, subclass
      puts "Added subclass #{subclass_name} -> #{subclass}"
    end

    def inherited(subclass)
      name = subclass.name.downcase
      self.add_subclass(name.to_sym, subclass)
    end

  end

  module Factory
    class << self

      def [](name)
        Driver.list[name] || Driver
      end

    end
  end
end

class SuperDuper < Driver
end

class Bubbles < Driver
end

puts Driver.list

p Driver::Factory[:superduper].new

p Driver::Factory[:bubbles].new

p Driver::Factory[:oopsy].new