document.createTouch.length
  

Result:

    document.createTouch(window, window, 1, 15, 20, 35);
  

Result:

    document.createTouch(window, window, 1, 15, 20, 35, 40);
  

Result:

    document.createTouch(window, window, 1, 15, 20, 35, 40, 1, 2, 3);
  

Result: