対話によるCommon Lisp入門 30 末尾再帰 その2

[6]> (defun factorial (n)
(factorial-loop n 1 1))
FACTORIAL
[7]> (defun factorial-loop (n i p)
(if (> i n) p
(factorial-loop n (+ i 1) (* p i))))
FACTORIAL-LOOP
[8]> (factorial 4)
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