Hi Karl,
At 01:00 PM 7/22/2004, you wrote:
I have a param which is populated with an XML source.
The paramter is declared like this:
<xsl:param name="ENTRY_TEMPLATE" select="/"/>
My top level match is:
<xsl:template match="/">
Within this template rule I apply the following:
<xsl:apply-templates select="$ENTRY_TEMPLATE"/>
If the param ENTRY_TEMPLATE is not set, I end up with an infinite loop. Is
this normal behaviour? I'm guessing that maybe it is bad practice to
declare the param as I have.
It is normal behavior, since when your parameter is set to the root,
selecting it and applying templates applies the template matching the root
... etc. ad infinitum.
But it's easy enough to set the parameter's default to something else. A
node set containing no nodes will do nicely ... you could
select="/parent::*" (or select="/.." if you prefer), which selects the
parent of the root -- which doesn't exist. Accordingly in such cases
templates will be applied to nothing, thereby avoiding the problem of the
template selecting its own current node to apply itself to (thus selecting
its own current node).
A more robust solution could actually trap the troublesome case by testing
whether the parameter identifies the root:
<xsl:when test="generate-id(/) = generate-id($ENTRY_TEMPLATE)">
<xsl:message>Sorry, can't process the root as entry template</xsl:message>
</xsl:when>
<xsl:otherwise>
<xsl:apply-templates select="$ENTRY_TEMPLATE"/>
</xsl:otherwise>
Cheers,
Wendell
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Wendell Piez
mailto:wapiez(_at_)mulberrytech(_dot_)com
Mulberry Technologies, Inc. http://www.mulberrytech.com
17 West Jefferson Street Direct Phone: 301/315-9635
Suite 207 Phone: 301/315-9631
Rockville, MD 20850 Fax: 301/315-8285
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