def merge_element!(hash, element, depth)
        raise REXML::ParseException, "The document is too deep" if depth == 0
        merge!(hash, element.name, collapse(element, depth))
      end
def merge_element!(hash, element, depth)
        raise REXML::ParseException, "The document is too deep" if depth == 0
        merge!(hash, element.name, collapse(element, depth))
      end
Convert an XML element and merge into the hash

 hash::
   Hash to merge the converted element into.
 element::
   XML element to merge into hash