Clojure: Avoiding stack overflow in Sieve of Erathosthene?

Posted by nixx on Stack Overflow See other posts from Stack Overflow or by nixx
Published on 2010-06-07T18:34:07Z Indexed on 2010/06/07 19:22 UTC
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Here's my implementation of Sieve of Erathosthene in Clojure (based on SICP lesson on streams):

(defn nats-from [n]
  (iterate inc n))

(defn divide? [p q]
  (zero? (rem q p)))

(defn sieve [stream]
  (lazy-seq (cons (first stream)
            (sieve (remove #(divide? (first stream) %) 
               (rest stream))))))

(def primes (sieve (nats-from 2)))

Now, it's all OK when i take first 100 primes:

(take 100 primes)

But, if i try to take first 1000 primes, program breaks because of stack overflow. I'm wondering if is it possible to change somehow function sieve to become tail-recursive and, still, to preserve "streamnes" of algorithm?

Any help???

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