function factorial(x)
{
  if (x <= 1) {
    return 1;
  }
  else {
    return x * factorial(x-1);
  }
}

function not_a_random_number_generator(max) {
  local last = 42;
  local IM = 139968;
  local IA = 3877;
  local IC = 29573;
  for(;;) { // loops forever
    yield (max * (last = (last * IA + IC) % IM) / IM);
  }
}

local randtor = not_a_random_number_generator(100);

for(local i = 0; i < 10; i += 1)
   print(">"+resume randtor+"\n");

class BaseVector {
  constructor(...)
  {
    if(vargv.len() >= 3) {
      x = vargv[0];
      y = vargv[1];
      z = vargv[2];
    }
  }
  x = 0;
  y = 0;
  z = 0;
}

class Vector3 extends BaseVector {
  function _add(other)
  {
    if(other instanceof ::Vector3)
      return ::Vector3(x+other.x,y+other.y,z+other.z);
    else
      throw "wrong parameter";
  }
  function Print()
  {
    ::print(x+","+y+","+z+"\n");
  }
}

local v0 = Vector3(1,2,3)
local v1 = Vector3(11,12,13)
local v2 = v0 + v1;
v2.Print();