pan> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">attrN</span><span class="special">);</span>

    <span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">Expr</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">Delimiter</span>
      <span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">Attr1</s