# File lib/dm-core/model.rb, line 224
    def inherited(descendant)
      descendants << descendant

      descendant.instance_variable_set(:@valid,         false)
      descendant.instance_variable_set(:@base_model,    base_model)
      descendant.instance_variable_set(:@storage_names, @storage_names.dup)
      descendant.instance_variable_set(:@default_order, @default_order.dup)
    end