title: How to create default value for function argument in Clojure
body: <p>I come with this:</p>
  <pre class="lang-clj prettyprint-override"><code>(defn string-&gt;integer [str &amp; [base]]
    (Integer/parseInt str (if (nil? base) 10 base)))
  
  (string-&gt;integer &quot;10&quot;)
  (string-&gt;integer &quot;FF&quot; 16)
  </code></pre>
  <p>But it must be a better way to do this.</p>