sp;an]&nbsp;[b1;&nbsp;...;&nbsp;bm]</code> performs
    a lexicographic comparison of the two input lists,
    using the same <code class="code">'a&nbsp;-&gt;&nbsp;'a&nbsp;-&gt;&nbsp;int</code> interface as <a href="Stdlib.html#VALcompare"><code class="code">compare</code></a>:</p>

<ul>
<li><code class="code">a1&nbsp;::&nbsp;l1</code> is smaller than <code class="code">a2&nbsp;::&nbsp;l2</code> (negative result)
      if <code class="code">a1</code> is smaller than <code class="code">a2</code>, or if they 