tt>no_actions_d</tt> directive tweaks the scanner to disable firing 
  semantic actions. Like before, all parsers inside the <tt>no_actions_d</tt> 
  gets a transformed scanner type. If a rule must be used inside a <tt>no_actions_d</tt>, 
  the rule's type must be:</p>
<pre>    <span class=identifier>rule</span><span class=special>&lt;</span>no_actions_scanner<span class="special">&lt;</span><span class=identifier>ScannerT</span><span class=special>&gt;::</span><span class="identifier">type</span><span clas