def search_current_el xpath
      # try to find the rule in the current verb
      desired_el = @current_el.at_xpath xpath
      return desired_el unless desired_el.nil?
      
      # check all the verb's parents, walking up the hierarchy
      @current_el_parents.each do |parent|
        desired_el = parent.at_xpath xpath
        return desired_el unless desired_el.nil?
      end
      
      nil
    end
def search_current_el xpath
      # try to find the rule in the current verb
      desired_el = @current_el.at_xpath xpath
      return desired_el unless desired_el.nil?
      
      # check all the verb's parents, walking up the hierarchy
      @current_el_parents.each do |parent|
        desired_el = parent.at_xpath xpath
        return desired_el unless desired_el.nil?
      end
      
      nil
    end
Search each parent of some verb for a given element.
 Used for rule inheritance.