:
      </p>
<pre class="programlisting"><span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Tag</span><span class="special">&gt;</span>
<span class="keyword">struct</span> <span class="identifier">basic_message</span> <span class="special">{</span>
 <span class="keyword">public</span><span class="special">:</span>
  <span class="keyword">typedef</span> <span class="identifier">Tag</span> <span class="identifier">tag</span><span 