def __init__(self, pattern: str, invert_match: bool = False,
error_tag: str = None,
error_message: str = None):
"""Initialize the class instance."""
super().__init__(error_tag, error_message if error_message else
"pattern '{}'".format(pattern))
self.pattern = pattern
self.invert_match = invert_match
try:
self.regex = re.compile(XMLToPython(pattern))
except RegularExpressionError:
raise InvalidArgument(pattern) from None
def _eval(self, xctx: XPathContext) -> bool:
lres, rres = self._eval_ops_string(xctx)
try:
return re.match(XMLToPython(rres), lres) is not None
except RegularExpressionError:
raise InvalidArgument(rres) from None