// If one operand is the undefined or undefined value, it is treated as having the type of the // other operand. enum E { a, b } var a: any; var b: number; // operator * var rk1 = undefined ** a; var rk2 = undefined ** b; var rk3 = undefined ** 1; var rk4 = undefined ** E.a; var rk5 = a ** undefined; var rk6 = b ** undefined; var rk7 = 0 ** undefined; var rk8 = E.b ** undefined;