StateCache Meta'd up

gistfile1.rb

#==============================================================================
# ** Module TDD::StateCache
#------------------------------------------------------------------------------
#  This module provides methods that allow a class to easily cache its method
#  calls for more dynamic state handling without using instance variables
#==============================================================================
module TDD
module StateCache
  #--------------------------------------------------------------------------
  # * Extend Included Call with Class Methods
  #--------------------------------------------------------------------------
  def self.included base
    base.extend ClassMethods
  end
  module ClassMethods
    #--------------------------------------------------------------------------
    # * Define Method as Cached
    #--------------------------------------------------------------------------
    def cached_method(original_method)
      # Setup alias
      aliased_method = "cached_#{original_method}".to_sym
      alias_method aliased_method, original_method

      # Define cached method
      define_method(original_method) do
        return state_cache[original_method] if state_cache[original_method]
        state_cache[original_method] = send(aliased_method)
      end
    end
  end
  #--------------------------------------------------------------------------
  # * State Cache Store
  #--------------------------------------------------------------------------
  def state_cache
    @state_cache ||= {}
  end
end
end

# Testing it
class A
  include TDD::StateCache

  def test
    return Random.rand(999)
  end; cached_method(:test)

end

instance = A.new
puts instance.test
puts instance.test
instance.state_cache.clear
puts instance.test

instance_2 = A.new
puts instance_2.test
instance_2.state_cache.clear
puts instance_2.test