">unsigned</span></code> attribute:
      </p>
<pre class="programlisting"><span class="comment">// grammar definition</span>
<span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">Iterator</span><span class="special">&gt;</span>
<span class="keyword">struct</span> <span class="identifier">roman</span> <span class="special">:</span> <span class="identifier">qi</span><span class="special">::</span><span class="identifier">grammar<