title: Making a list of unbound variables (LISP)
body: <p>I have the following LISP code</p>
  
  <pre><code>(defun l (x y) (list x y))
  </code></pre>
  
  <p>when I do <code>(l a a)</code> I get an error that A has no value.</p>
  
  <p>I want this to return (a a). How can I overcome this?</p>