(module usage (make-usage)

(import chicken scheme ports)
(use files)

(define (make-usage helper)
  (lambda (#!optional exit-code)
    (with-output-to-port
        (if (or (not exit-code)
                (zero? exit-code))
            (current-output-port)
            (current-error-port))
      (lambda ()
        (helper (pathname-strip-directory (program-name)))))
    (when exit-code (exit exit-code))))

); end module