des</span><span class="p">(</span><span class="nx">nested</span><span class="p">))</span><span class="w"> </span><span class="p">{</span>
<span class="w">  </span><span class="nx">console</span><span class="p">.</span><span class="nx">log</span><span class="p">(</span><span class="nx">value</span><span class="p">)</span>
<span class="p">}</span>
</code></pre></div>
</div>
<p>Let&rsquo;s use generators to count the number of expressions of various types in a program.
The generator function that visits each n