title: I got "scheme application not a procedure" in the last recursive calling of a function
body: <p>so here is the code:</p>
  
  <pre><code>(define (time-prime-test n)
    (newline)
    (display n)
    (start-prime-test n (runtime)))
  
  (define (start-prime-test n start-time)
    (if (prime? n)
        (report-prime (- (runtime) start-time))))
  
  (define (report-prime elapsed-time)
    (display " *** ")
    (display elapsed-time))
  
  (define (search-for-primes n m)
    (if (&lt; n m) 
        ((time-prime-test n)
         (search-for-primes (+ n 1) m))
        (display " calculating stopped. ")))
  (search-for-primes 100000 100020)
  </code></pre>
  
  <p>and i got this error after "calculating stopped." has been displayed. like below:</p>
  
  <blockquote>
    <p>100017 
    100018 
    100019 <em>*</em> 54 calculating stopped. . . application: not a procedure;  expected a procedure that can be applied to arguments<br>
    given: #&lt;void><br>
    arguments...:<br>
     #&lt;void></p>
  </blockquote>