(function factorial [
  (default-space:space-address <- new space:literal 30:literal)
  (n:integer <- next-input)
  { begin
    ; if n=0 return 1
    (zero?:boolean <- equal n:integer 0:literal)
    (break-unless zero?:boolean)
    (reply 1:literal)
  }
  ; return n*factorial(n-1)
  (x:integer <- subtract n:integer 1:literal)
  (subresult:integer <- factorial x:integer)
  (result:integer <- multiply subresult:integer n:integer)
  (reply result:integer)
])

(function main [
  (1:integer <- factorial 5:literal)
  ($print (("result: " literal)))
  (print-integer nil:literal/terminal 1:integer)
  ($print (("\n" literal)))
])