More general question about lazy behaviour

[Richard R. McKinley]

In lazy evaluation, as implemented in Xalan-J,  with this example what 
will the value of month be?  My observation is that the <xsl:choose> 
actions definately cause the Java add() method to be called 
immediately.  This is what I want.  Now, when I reference $month later 
on, I get the values of $selected-calendar *prior* to the <xsl:choose> 
actions.  This is exactly what I want, but is this the way that lazy 
evaluation should work?  You see, by the time I reference the value of 
$month, the underlying object has changed values to a previous month.  
Prior to the <xsl:choose> actions I never evaluate the value of $month.  
I would expect that lazy evaluation would give me the current values of 
$selected-calendar and not the values from before <xsl:choose>.  To 
recap, it is behaving the way I want it to, but can I rely on that 
behaviour under the rules of lazy evaluation?  And, as always, I 
appreciate your help with this :)

<xsl:variable name="selected-calendar" select="java:clone($calendar)"/>
<xsl:variable name="first-day-of-week" 
select="java:get($selected-calendar, $day-of-week-field-value)"/>
<xsl:variable name="month" select="java:get($selected-calendar, 
$month-field-value)"/>
<xsl:variable name="year" select="java:get($selected-calendar, 
$year-field-value)"/>
   <xsl:choose>
      <xsl:when test="$first-day-of-week = 1">
         <xsl:if test="java:add($selected-calendar, $date-field-value, 
-8)"/>
       </xsl:when>
       <xsl:otherwise>
         <xsl:if test="java:add($selected-calendar, $date-field-value, 
(-1 * $first-day-of-week))"/>
       </xsl:otherwise>
   </xsl:choose>