I have a question about the insertion sort algorithm implemented in chapter 12.The figure 33 explains<br><br><pre class="scheme"><span class="comment">;; <code class="scheme"><span class="variable">sort</span> <span class="selfeval">:</span> <span class="variable">list-of-numbers</span>  <tt>-&gt;</tt>  <span class="variable">list-of-numbers</span> (<span class="variable">sorted</span>)</code></span><br>
<span class="comment">;; to create a list of numbers with the same numbers as</span><br><span class="comment">;; <code class="scheme"><span class="variable">alon</span></code> sorted in descending order</span><br>(<span class="keyword">define</span> (<span class="variable">sort</span> <span class="variable">alon</span>)<br>
  (<span class="keyword">cond</span><br>    [(<span class="builtin">empty?</span> <span class="variable">alon</span>) <span class="builtin">empty</span>]<br>    [(<span class="builtin">cons?</span> <span class="variable">alon</span>) (<span class="variable">insert</span> (<span class="builtin">first</span> <span class="variable">alon</span>) (<span class="variable">sort</span> (<span class="builtin">rest</span> <span class="variable">alon</span>)))]))- what is cons? alon here , is it required there?<br>
<br><br>Thanks<br><br>Aditya<br><br><br><br><br><br><br></pre><br>