def match(self, string):
        """
        Match the string with the grammar.
        Returns a :class:`Match` instance or `None` when the input doesn't match the grammar.

        :param string: The input string.
        """
        m = self._re.match(string)

        if m:
            return Match(string, [(self._re, m)], self._group_names_to_nodes, self.unescape_funcs)
Match the string with the grammar.
        Returns a :class:`Match` instance or `None` when the input doesn't match the grammar.

        :param string: The input string.