module MediaShelfClassLevelInheritableAttributes::MSClassMethods

def inherited(subclass)
  @ms_inheritable_attributes.each do |attrib|
    instance_var = "@#{attrib}"
    subclass.instance_variable_set(instance_var, instance_variable_get(instance_var))
  end
end

def ms_inheritable_attributes(*args)
  @ms_inheritable_attributes ||=[:ms_inheritable_attributes]
  @ms_inheritable_attributes+=args
  args.each do |arg|
    class_eval %(
      class <<self;attr_accessor :#{arg} end
    )
  end
  @ms_inheritable_attributes
end