sandbox-lazy-seq.clj

(defn lazy-inc [x]
  (lazy-seq
   (print ".")
   (cons x (lazy-inc (inc x)))))

(print "\n take 2: ")
(take 2 
      (lazy-inc 1))

(print "\n first: ")
(first 
 (lazy-inc 1))

(print "\n 2 first odds: ")
(take 2 
      (filter odd? (lazy-inc 1)))

(print "\n first > 3: ")
(first 
 (drop-while #(>= 3 %) (lazy-inc 1)))

(print "\n 2 first odds > 3: ")
(take 2 
      (filter odd? 
              (drop-while #(>= 3 %) (lazy-inc 1))))

(defn lazy-pairs [x] 
  (lazy-seq (print ".")
   (cons [x x] (lazy-pairs (inc x)))))

(print "\n 2 first lazy pairs which sum > 3: ")
(take 2 
      (drop-while #(> 10 (reduce + %)) (lazy-pairs 1)))