// CS0019: Operator `==' cannot be applied to operands of type `Foo' and `null' // Line: 14 struct Foo { public static bool operator == (int d1, Foo d2) { throw new System.ApplicationException (); } public static bool operator != (int d1, Foo d2) { throw new System.ApplicationException (); } } public class Test { static Foo ctx; public static void Main () { if (ctx == null) return; } }