Re: Simple recursive functions in Lisp

B. Pym wrote:

Pascal Bourguignon wrote:
 

(defun sum (list)
  (loop :for x :in list :sum x))

 
Gauche Scheme
 
(define (sum lst)   (fold + 0 lst))
 
(sum '(1 3 5 7 9))
  ===>
25

Pascal Bourguignon wrote:

Of course, since LOOP is a higher level abstraction.  You should
compare with this iterative form:
>
(defun sum (list)
  (do ((current list (cdr current))
       (sum 0))
      ((null current) sum)
   (setf sum (+ sum (car current)))))

Better:

(define (sum lst)
  (do ((xs lst (cdr xs))
       (res 0 (+ res (car xs))))
    ((null? xs)  res)))