shirok

(use gauche.generator)
;
#|
Scheme:generatorとdoとwhile
http://practical-scheme.net/wiliki/wiliki.cgi?Scheme%3agenerator%e3%81%a8do%e3%81%a8while#H-17qe7ru
|#
(define (generator-generate proc)
  (define next #f)
  (define return #f)
  (lambda ()