anchor.diff:           (example-file (make-pathname :name "example"
                                            :type "lisp"
                                            :defaults exercise-directory)))
  -    (write-production-code example-file test-data)))
  +    (write-production-code example-file test-data)
  +        (format *standard-output* "Wrote ~A~&" example-file)))
   
   (defun generate (exercise)
     (let ((test-data (read-exercise-data (canonical-data-pathname exercise))))
  
positive.code:     (format stream "~%~%")))
  
  (defun make-exercise-directory (test-data)
    (ensure-directories-exist
     (exercise-directory-pathname (exercise-name test-data))))
  
  (defun make-test-code (test-data)
    (let* ((exercise (exercise-name test-data))
  
negative.code:                             :if-exists :supersede)
        (write-prologue stream test-data)
        (write-tests stream test-data)
        (write-epilogue stream test-data))
      (format *standard-output* "Wrote ~A~&" test-file)))
  
  (defun write-production-code (file test-data)
    (with-open-file (stream file
  