min, max

;; fundamental predefined Lisp functions

;(debug t)

(defun max (&rest numargs)

  "return the biggest of all (numeric) arguments"

  (if (null (cdr numargs))

      (car numargs)

    (let ((a (car numargs))

          (b (apply #'max (cdr numargs))))

      (if (< a b)

          b

        a))))

(defun min (&rest numargs)

  "return the smallest of all (numeric) arguments"

  (if (null (cdr numargs))

      (car numargs)

    (let ((a (car numargs))

          (b (apply #'min (cdr numargs))))

      (if (< a b)

          a

        b))))

(defun apropos (match)

  (sort (filter #'(lambda (sym) (re-match match (symbol-name sym)))

                (symbols))

  * more of alists

  * min, max; floor ceiling, round

  * floor, ceiling, round

  + min, max

  + "isqrt", "return the integer square root of numeric ARG"

(testcmp "max 1" '(max) nil)

(testcmp "max 2" '(max 3) 3)

(testcmp "max 3" '(max 3 4 5 2 54 6 9 3 5 7) 54)

(testcmp "max 4" '(max 3 -4 5 -2 54 -6 9 -3 5 -7) 54)

(testcmp "min 1" '(min) nil)

(testcmp "min 2" '(min 3) 3)

(testcmp "min 3" '(min 3 4 5 2 54 6 9 3 5 7) 2)

(testcmp "min 4" '(min 3 -4 5 -2 54 -6 9 -3 5 -7) -7)

(testcmp "min 5" '(min 4 2 4 2 4 2 7 1 19) 1)