path: root/archive/0.vm.arc/tangle.mu

; To demonstrate tangle directives, we'll construct a factorial function with
; separate base and recursive cases. Compare factorial.mu.
; This isn't a very realistic example, just a simple demonstration of
; possibilities.

(function factorial [
  (default-space:space-address <- new space:literal 30:literal)
  (n:integer <- next-input)
  { begin
    base-case
  }
  recursive-case
])

(after base-case [
  ; if n=0 return 1
  (zero?:boolean <- equal n:integer 0:literal)
  (break-unless zero?:boolean)
  (reply 1:literal)
])

(after recursive-case [
  ; 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-character nil:literal/terminal ((#\newline literal)))
])