cluded inside code strings delimited by 
<tt>{:</tt> and <tt>:}</tt>.  In addition, labels have been placed on various 
symbols in the right hand side of productions.  For example in:<br>
<pre>  expr:e1 PLUS expr:e2    
	{: RESULT = new Integer(e1.intValue() + e2.intValue()); :} 
</pre>
<a name="RES_part"></a>
the first non-terminal <tt>expr</tt> has been labeled with <tt>e1</tt>, and 
the second with <tt>e2</tt>.  The left hand side value 
of each production is always implicitly labeled as <tt>RESULT</tt>.