// CS0457: Ambiguous user defined conversions `A.implicit operator byte(A)' and `A.implicit operator sbyte(A)' when converting from 'A' to 'int' // Line: 20 class A { public static implicit operator sbyte (A mask) { return 1; } public static implicit operator byte (A mask) { return 2; } } class X { static A a = null; static object o = ~a; }