janet/examples/primes.dst

# Return an array of primes. This is a trivial and extremely naive algorithm.

(defn primes
 "Returns a list of prime numbers less than n."
 [n]
 (def list @[])
 (for [i 2 n]
  (var isprime? true)
  (def len (length list))
  (for [j 0 len]
   (def trial (get list j))
   (if (zero? (% i trial)) (:= isprime? false)))
  (if isprime? (array-push list i)))
 list)