() test() {
    
    var int a = 1;
    /* ERRORS only pointer types are compatible without "makeopt" */
    var int? b = 2;
    var int?? c = b;
    b = a;
    c = a;
    b = 3;
    c = 4;
    c? = 5;
    
    var int^? p = @a;
    var int^ q = p; // ERROR assigning optional type to non-optional type
    
    var (int^? x) optstruct = (@a,);
    var (int^ x) ptrstruct;
    
    ptrstruct = optstruct; // ERROR
}