// CS0019: Operator `==' cannot be applied to operands of type `A' and `int?' // Line: 22 class A { public static bool operator == (A a, int b) { return false; } public static bool operator != (A a, int b) { return false; } } class C { public static void Main () { A a = new A (); object b = a == Id; } static int? Id { get { return 1; } } }