try { function f() {} f("".match(/(?:(?=g)).{2147483648,}/ + (/[]/)), null); } catch (e) {} // Yarr throws on the above regexp var re = new RegExp("a[\x01-\\xDE]+M", "gi"); re.exec(""); var re = new RegExp("a[\x01-\\u00b8]+?c", "gi"); re.exec(""); var re = new RegExp("a[\x01-\\u00f8]?c", "gi"); re.exec("");