<span class="special">::</span><span class="identifier">val</span><span class="special">(</span><span class="string">"Error!"</span><span class="special">));</span>
</pre>
<p>
          If you fail to do so the resulting code will trigger an assert statement
          at runtime.
        </p>
</td></tr>
</table></div>
<p>
        Any rule that repeats, such as kleene_star (<code class="computeroutput"><span class="special">*</span><span class="identifier">a</span></code>) or positive such as (<code class="c