def concat (objects)
      objects = objects.collect do |obj|
        obj = @klass.new(obj) if obj.is_a?(Hash)
        raise ArgumentError.new("#{obj.inspect} is not a #{@klass}") unless obj.is_a?(@klass)
        obj.parent = @parent
        obj
      end
      super(objects)
    end
def concat (objects)
      objects = objects.collect do |obj|
        obj = @klass.new(obj) if obj.is_a?(Hash)
        raise ArgumentError.new("#{obj.inspect} is not a #{@klass}") unless obj.is_a?(@klass)
        obj.parent = @parent
        obj
      end
      super(objects)
    end
Concatenate an array of objects to the array. The objects must either be an EmbeddedDocument of the
 correct class, or a Hash.