class Vector3
{
  // you can use attr, auto or var in this context
  attr x
  auto y
  var z

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

  def doSomething(mult)
  {
    return this.x * this.y * this.z * mult
  }

}


auto v = Vector3(1,2,3)
assert_equal(1, v.x)
assert_equal(v.doSomething(2), 12)