   </h3>
<a name="adaption_of_qring_source_code"></a><pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span>
<span class="special">{</span>
    <span class="keyword">namespace</span> <span class="identifier">geometry</span>
    <span class="special">{</span>
        <span class="keyword">namespace</span> <span class="identifier">traits</span>
        <span class="special">{</span>
            <span class="keyword">template</span><span class="special">&lt;&gt;