title: Extracting element from a list in Scheme
body: <p>I want to extract the element '42' using only 'car' and 'cdr' in Scheme</p>
  <pre><code>(car (car ((0) (42 #t) (bar))))
  </code></pre>
  <p>However, I get an error message:</p>
  <pre><code>application: not a procedure; 
  expected a procedure that can be applied to arguments 
  given: 0 
  arguments.....: [none]&quot;
  </code></pre>