identifier">duplicate</span><span class="special">;</span>
<span class="keyword">using</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">karma</span><span class="special">::</span><span class="identifier">space</span><span class="special">;</span>
</pre>
<p>
          </p>
<p>
            Basic usage of the <code class="computeroutput"><span class="identifier">duplicate</span></code>
      