Clojure lazy sequences.

(range 2 7)
(range 6)
;; An infinite range:
(take 5 (range))
(class (range 2 7))
(class (range))
(def evens (filter even? (range)))
(take 5 evens)
(take 5 (map #(* % %) evens))

;; how to create your own infinite lazy sequences:
(take 10 (repeat 3))
(take 10 (iterate #(* 2 %) 1))

;; many higher-order functions return lazy sequences:
(take 10 (map inc (iterate #(* 2 %) 1)))
(take 10 (interleave (iterate #(* 2 %) 1) (iterate #(* 3 %) 1)))

;; you can store lazy sequences in variables:
(def all-natural-numbers (range))

;; note: reduce is not lazy (it is eager):
;; this will go into an infinite computation:
;(def sum-of-everything (reduce + (range)))

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