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<h3 class="unnumberedsec">How can I make REJECT cascade across start condition boundaries?</h3>

<p>You can do this as follows.  Suppose you have a start condition &lsquo;<samp>A</samp>&rsquo;, and
after exhausting all of the possible matches in &lsquo;<samp>&lt;A&gt;</samp>&rsquo;, you want to try
matches in &lsquo;<samp>&lt;INITIAL&gt;</samp>&rsquo;.  Then you could use the following:
</p>
<div class="example">
<pre class="verbatim">%x A
%%
&lt;A&gt;rule_that_is_long    ...; REJECT;
&lt;A&gt;rule                 ...; REJECT; /* shorter rule */
&lt;A&gt;etc.
...
&lt;A&gt;.|\n  {
/* Shortest and last rule in &lt;A&gt;, so
* cascaded REJECTs will eventually
* wind up matching this rule.  We want
* to now switch to the initial state
* and try matching from there instead.
*/
yyless(0);    /* put back matched text */
BEGIN(INITIAL);
}
</pre></div>




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flex-doc 2.6.4-6 / usr / share / doc / flex-doc / html / How-can-I-make-REJECT-cascade-across-start-condition-boundaries_003f.html
