; a little helper method that just adds one
; to an accumulator when given an x
(defun mycount (acc x) (+ acc 1))

; define length-list using a left fold
(defun length-list (xs)
    (reduce #'mycount xs :initial-value 0)
)

; see? it works!
(length-list '(a b c d e f g))

; we should get 7
(quit)