fizzbuzz.lisp

(defun fizzbuzz-simple (n)
  "simple implementation"
  (do ((i 1 (1+ i)))
      ((> i n))
    (cond ((and (= (mod i 3) 0) (= (mod i 5) 0)) (format t "fizzbuzz~%"))
	  ((= (mod i 3) 0) (format t "fizz~%"))
	  ((= (mod i 5) 0) (format t "buzz~%"))
	  (t (format t "~D~%" i)))))

(defun fizzbuzz-when (n)
  (labels ((fizz-buzz-integer (k)
	     (let ((p 0))
	       (format t "~T")
	       (when (zerop (mod k 3)) (format t "fizz") (incf p))
	       (when (zerop (mod k 5)) (format t "buzz") (incf p))
	       (when (zerop p) (format t "~A" k)))))
    (dotimes (i n)
      (fizz-buzz-integer (1+ i)))))

(defun fizzbuzz-strict-nor (n)
  "implementation using nor with strict evaluation"
  (labels ((princ-strict-nor (k &rest tests)
	     (when (every #'null tests) (princ k))))
    (do ((i 1 (1+ i)))
	((> i n))
      (princ-strict-nor i
		      (if (= (mod i 3) 0) (princ "fizz"))
		      (if (= (mod i 5) 0) (princ "buzz")))
      (format t "~%"))))

(defmacro generalized-fizzbuzz (n &rest pairs-div-str)
  "generalized implementaion based on fizzbuzz-strict-nor"
  (let ((cnt (gensym))
	(lst-if nil))
    (dolist (lst (sort pairs-div-str #'> :key #'car))
      (push `(if (= (mod ,cnt ,(car lst)) 0) (princ ,(cadr lst)))
	    lst-if))
    `(labels ((princ-strict-nor (k &rest tests)
		(when (every #'null tests) (princ k))))
       (do ((,cnt 1 (1+ ,cnt)))
	   ((> ,cnt ,n))
	 (princ-strict-nor ,cnt ,@lst-if)
   	 (format t "~%")))))