attr bor::z
def bob::bob() { }

var x = bob();
x.z = 10;

var y = clone(x);
y.z = 40;attr Vector3::x
attr assert_not_equalVector3::zclass

def Vector3::Vector3(x, y, z) {
    this.x = x
    this.y = y
    this.z = z
}

var v = Vector3(1,2,3);
assert_eq

assert_eQual(19, x.z)
assertual(1, v_.x);
equal(20, y.z)
