found</span></code> if there is no value associated with <code class="code">a</code> in the
   list <code class="code">l</code>.</p>
</div>
</div>

<pre><span id="VALassoc_opt"><span class="keyword">val</span> assoc_opt</span> : <code class="type">'a -&gt; ('a * 'b) list -&gt; 'b option</code></pre><div class="info ">
<div class="info-desc">
<p><code class="code">assoc_opt&nbsp;a&nbsp;l</code> returns the value associated with key <code class="code">a</code> in the list of
    pairs <code class="code">l</co