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Why flaws are needed to prevent infinite recursion

When defining an infinite sequence, I noticed that cons are needed to avoid infinite recursion. However, I do not understand why. Here is the code in question:

(defn even-numbers
  ([] (even-numbers 0))
  ([n] (cons n (lazy-seq (even-numbers (+ 2 n))))))

(take 10 (even-numbers))
;; (0 2 4 6 8 10 12 14 16 18)

This works great; but since I like to ask questions, I started wondering why the cons are needed (except for the inclusion of 0). In the end, the lazy-seq function creates lazy seq. This means that the rest of the values ​​should not be calculated until they are called (or separated). So I tried it.

(defn even-numbers-v2
  ([] (even-numbers-v2 0))
  ([n] (lazy-seq (even-numbers-v2 (+ 2 n)))))

(take 10 (even-numbers-v2))
;; Infinite loooooooooop

So now I know that cons are needed, but I would like to know why cons are needed for a lazy assessment of an allegedly lazy sequence.

+4
1

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