@main = function() {
  call @factorial [5] %return
}
@factorial = function(%n) {
  op!== %n 0 %notZero
  jmpif %notZero :recurse
  mov 1 %return
  end
recurse:
  op- %n 1 %nMinus1
  call @factorial [%nMinus1] %previousFactorial
  op* %n %previousFactorial %return
}