The keywork to come out of the loop abruptly

sayanand · February 23rd, 2009, 04:24 PM

hi,

If I want to come out of the <xsl:for-each ...> loop or any template on some condition, how can i come out of that?

The keywork "break" in Java helps to achieve this.

Any one can help me on this.

mhkay · February 23rd, 2009, 05:08 PM

Whereas a "for" expression in Java is a loop in which the items must be processed sequentially, a for-each instruction in XSLT is a mapping expression in which the items in the input can be processed in any order or in parallel. It's not a loop, so it doesnt' make sense to break out of it. If you need to process items until some condition is true, use a recursive template or function.

sayanand · March 2nd, 2009, 03:54 PM

hi,
Thanks for the reply.

I have used the recursive loop. But still i am not able to come out when i like to.
PFB the code snippet.

<?xml version="1.0"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:template match="/">
<xsl:call-template name="one">
<xsl:with-param name="st" select="0"/>
<xsl:with-param name="end" select="5"/> </xsl:call-template>
</xsl:template>

<xsl:template name="one">
<xsl:param name="st"/>
<xsl:param name="end"/> <xsl:if test="$st = 3 ">
<xsl:text>Inside... Exit now</xsl:text> </xsl:if>
<xsl:if test="$st < $end">
<xsl:call-template name="one">
<xsl:with-param name="st" select="$st + 1"/>
<xsl:with-param name="end" select="$end"/> </xsl:call-template>
</xsl:if>
</xsl:template>
</xsl:stylesheet>

The templae "one" will be recursively called until the condition $st = 3 is satisfied. Once the condition is satisfied, I have to come out of it. How to do that. I tried declaring some variable and assigned some junk value. But as this is declared inside the "if" block, its not visible outside.
Expecting the reply

joefawcett · March 2nd, 2009, 05:04 PM

I'm not sure why you're passing an end parameter and testing for $st = 3 but you could always use an xsl:choose construct:

Code:

<xsl:template name="one">
 <xsl:param name="st"/>
 <xsl:param name="end"/>
 <xsl:choose>
   <xsl:when test="$st &gt; $end ">
    <xsl:text>Exit now</xsl:text>
   </xsl:when>
   <xsl:otherwise>
      $st: <xsl:value-of select="$st" />,      <xsl:call-template name="one">
       <xsl:with-param name="st" select="$st + 1"/>
         <xsl:with-param name="end" select="$end"/>
     </xsl:call-template>
   </xsl:otherwise>
 </xsl:choose>
</xsl:template>

This will run until $st is greater than $end.

mhkay · March 2nd, 2009, 05:17 PM

As Joe's code shows, you don't have to do anything to exit. Just do nothing. I.e.

Code:

if (not finished) {
  make recursive call
}

and the exit is implicit