フィボナッチ数を求める関数を名前付きletで
(define (fib-let n) (let fib-loop((max n) (nth 0) (n1 0) (n2 1)) (if (>= nth max) n1 (fib-loop max (+ nth 1) n2 (+ n1 n2)))))
(define (fib-let n) (let fib-loop((max n) (nth 0) (n1 0) (n2 1)) (if (>= nth max) n1 (fib-loop max (+ nth 1) n2 (+ n1 n2)))))