gistfile1.builder

require 'logger'

module Loggable
  def self.included(klass)
    klass.extend ClassMethods
  end
  
  module ClassMethods
    def logger=(logger)
      @logger = logger
    end
    def logger
      @logger
    end
  end
    
  def logger
    self.class.logger
  end  
end

class Animal
  include Loggable
end

class Person
  include Loggable
  
  def die!
    logger.debug("Oh no I'm dying!")
  end
  
end



Person.logger = Logger.new(STDOUT)
Person.logger.debug "Hello world"
chad = Person.new
chad.die!