etry</span><span class="special">::</span><span class="identifier">interior_rings</span><span class="special">(</span><span class="identifier">poly</span><span class="special">).</span><span class="identifier">resize</span><span class="special">(</span><span class="number">1</span><span class="special">);</span>

    <span class="comment">// Append a range to the interior ring</span>
    <span class="identifier">append</span><span class="special">(</span><span class="identifier">poly</span><span class="spec