Re: simple loop question

Lars Brinkhoff wrote:

use LOOP to collect random integers into a list until the sum of that
list exceeds a constant (say 50).

 
(loop for x = (random 10) collect x sum x into y until (> y 50))

Let's see if it's shorter in Gauche Scheme.

(loop (y) (:coll (++. y (random 10))) (:till (> y 50)))

Yes, it is.

Given:

(use srfi-27)  ;; random-integer
(define random random-integer)

;; Returns the added number, not the sum.
(define-syntax ++.
  (syntax-rules ()
    [(++. place val)
     (let ((x val)) (set! place (+ x place))  x)]
    [(++. place)   (++. place 1)]))

I don't want to include the rather lengthy source for
"loop" here, so defining it is left as an exercise for
the reader.