gistfile1.clj

(def qq [ 1 -1 3 4 -4 -5 6 -10 1345 -32 ] )

(defn filter-neg[g]
  (if (neg? g)
       [ g (* -1 g)]))

(filter-neg 3)

(defn produce-with-fun[x prod-fun]
  (lazy-seq
    (when (seq x)
        (if-let [f (prod-fun (first x))]
            (cons f (red (rest x) prod-fun))
            (red (rest x) prod-fun)))))

(produce-with-fun qq filter-neg)