(define (any pred? arr)
     (call-with-current-continuation
       (lambda (exit)
         (for-each (lambda (x) (if (pred? x) (exit #t))) arr)
         #f)))

(set! pos? (lambda (x) (> x 0)))
(any pos? (list -1 -1 -1 -1 0 -2 -3 -4 -5 ))