n="baseline" colspan="1" align="left">
<nobr><var>subclassing-specifier</var> ::=</nobr> 
<a name="id2"></a></td><td valign="baseline" colspan="1" align="left"> <code>:plus-subclasses</code> | <code>:no-subclasses</code> | 
<code>+</code> | <code>=</code> </td></tr>
<tr>
<td valign="baseline" colspan="1" align="left"></td></tr></tbody></table>
<p>The shorthand <code>+</code> subclasses specifier is equivalent to
<code>:plus-subclasses</code> and <code>=</code> to <code>:no-subclasses</code>.
</p>
<p><span c