def __repr__(self):
        return "<NamedRequirements({}{})>".format(
            self.name,
            ", filename='{}'".format(self.filename.name) if self.filename
            else "")
def visitdir(self, dir):
        matched = self._matcher.match_recursive(dir)
        if matched is None:
            return True
        elif matched is True:
            return "all"
        else:
            assert matched is False
            return False