Generates a list containting the fibonacci-sequence out to n. It is also a memoizing function so a second call to the same n will be greatly faster.
1 2 3 (let ((cache (make-hash-table :test #'equal))) 4 (defun fibonacci-sequence (n) 5 "Calculates the a Fibonacci Sequence of n integers." 6 (declare (optimize speed)) 7 (declare (type number n)) 8 (labels ((get-fib (x seq) 9 (if (= x n) 10 (setf (gethash n cache) (nreverse seq)) 11 (if (cdr seq) 12 (get-fib (+ x 1) (push (+ (first seq) 13 (second seq)) 14 seq)) 15 (get-fib (+ x 1) (push 1 seq)))))) 16 (or (gethash n cache) 17 (get-fib 0 nil)))) 18 (defun fib-hash (n) 19 (gethash n cache)) 20 (defun fib-clear () 21 (setf cache (make-hash-table :test #'equal)))) 22
