30, you have been warned. ELEMENTS must be a generator which
will produce the elements."
(labels ((rec (&optional (current-depth 0))
- (let ((key (random (+ 3 (- depth current-depth)))))
+ (let ((key (random (+ 3 (- size current-depth)))))
(cond ((> key 2)
(list (rec (+ current-depth 1))
(rec (+ current-depth 1))))