title: How to return a default value with `cond` in PicoLisp
body: <p>I'm trying to return a default value when the other conditionals are not met with the <code>cond</code> statement. How can I achieve this in PicoLisp?</p>
  <pre><code>(de fib (n)
    (cond
      ((= n 0) 0)
      ((= n 1) 1)
      (+ (fib (- n 1)) (fib (- n 2))) ) )
  
  (prinl (fib 1)) # prints 1
  (prinl (fib 5)) # prints nothing
  (bye)
  </code></pre>
  <p><a href="https://picolisp.com/wiki/?home" rel="nofollow noreferrer">Example coded with this reference code</a>.</p>
  <pre><code>(let (Foo &quot;bar&quot;)
    (cond
      ((not Foo) &quot;No foo for you&quot;)
      ((lst? Foo) (map 'my-list-function Foo))
      ((= Foo &quot;bar&quot;) &quot;Foobar&quot;)
      &quot;Nothing is true&quot; ) )
  </code></pre>