def add_attribute(name, &block)
      declaration = Declaration::Dynamic.new(name, @ignore, block)
      @definition.declare_attribute(declaration)
    end
def add_attribute(name, &block)
      declaration = Declaration::Dynamic.new(name, @ignore, block)
      @definition.declare_attribute(declaration)
    end
Adds an attribute to the factory.
 The attribute value will be generated "lazily"
 by calling the block whenever an instance is generated.
 The block will not be called if the
 attribute is overridden for a specific instance.

 Arguments:
 * name: +Symbol+ or +String+
   The name of this attribute. This will be assigned using "name=" for
   generated instances.