1const Set0 = error{ A, B, C, D, E, F };
 2const Set1 = error{ F, E, D, C, A };
 3comptime {
 4    const x = Set0.B;
 5    const y: Set1 = @errorCast(x);
 6    _ = y;
 7}
 8
 9// error
10//
11// :5:21: error: 'error.B' not a member of error set 'error{A,C,D,E,F}'