ometry_object_model.boost_iterator_for_qring">Boost.Iterator
        for QRing</a>
      </h4>
<a name="adaption_of_qring_iterator_source_code"></a><pre class="programlisting"><span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">iterator</span><span class="special">/</span><span class="identifier">iterator_facade</span><span class="special">.</span><span class="identifier">hpp</span><span class