gem 'rasti-enum'

module Colors

  extend Rasti::Enum

  module Common
    def red?
      false
    end

    def green?
      false
    end

    def blue?
      false
    end
  end

  class Red < Rasti::Enum::Value
    include Common

    def red?
      true
    end
  end

  class Green < Rasti::Enum::Value
    include Common

    def green?
      true
    end
  end

  class Blue < Rasti::Enum::Value
    include Common

    def blue?
      true
    end
  end

end

Colors.values # => [Colors::Blue.new, Colors::Green.new, Colors::Red.new]

Colors.include?('GREEN') # => true
Colors.include?('WHITE') # => false

Colors['BLUE'].blue? # => true
Colors['BLUE'].red? # => false