;Chapter 7, Bryan Test 1, Page 119-121

(deftest test-streams ()
  (let* ( (path (make-pathname :name "myfile")) ;creates a path
          (str (open path :direction :output :if-exists :supersede))) ;opens a file for writing using the above name, it will overwrite if already exists
  (format str "This should be in the file~%") ;writes the string to the files
  (close str) ;closes the file
  (setf str (open path :direction :input))  ;reopens the file to read from.
  (check
    (equal (read-line str) "This should be in the file")))) ;makes sure that read line is equal to what we wrote.