def p_annotation_ref(self, p):
        """annotation_ref : AT ID NL
                          | AT ID DOT ID NL"""
        if len(p) < 5:
            p[0] = AstAnnotationRef(self.path, p.lineno(1), p.lexpos(1), p[2], None)
        else:
            p[0] = AstAnnotationRef(self.path, p.lineno(1), p.lexpos(1), p[4], p[2])