Recursion cont’d

(defun find-even (list)

(let ((item (first list)))

(if (and (numberp item)(evenp item))

item

(find-even (rest list)))))

(find-even '(5 7 8 9 11))

(trace find-even)

(find-even '(5 7 8 9 11))

Note problem: what if no evens?

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