(use data-generators test test-generative)

;; a generator is just a thunk so you're not bound to data-generators. You can
;; implement your own generators easily.
;; Incidently a generator in data-generator is just a thunk so it matches nicely 

(test-group "group around"
   (test-group "probably failing"
               
       (test-generative ((number (gen-fixnum))
                         (string (gen-string-of (gen-char #\a #\z))))
           (test-assert (> (string-length string) 30))
           (test-assert ((constantly #t)))))
   
       (test-group "all passing"
           (test-generative ((number (gen-fixnum)))
               (test-assert (number? number)))))
(test-exit)