d><p>The current expression </p></td>
</tr>
</tbody>
</table></div></td>
</tr>
<tr>
<td><p><span class="term">Returns:</span></p></td>
<td><p>
                  <code class="computeroutput">
                    context(typename Expr::proto_tag(),
                    <a class="link" href="../child_c.html" title="Function child_c">proto::child_c</a>&lt;0&gt;(expr),...
                    <a class="link" href="../child_c.html" title="Function child_c">proto::child_c</a>&lt;N&gt;(expr))
                  </code