code: def _uncached_match(self, text, pos, cache, error):
          
          m = self.re.match(text, pos)
          if m is not None:
              span = m.span()
              node = RegexNode(self, text, pos, pos + span[1] - span[0])
              node.match = m  # TODO: A terrible idea for cache size?
              return node
docs: Return length of match, ``None`` if no match.