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xsltxslt-1.0msxsl

Test for result tree fragment

I'm trying to create a template which either presents some content, or inserts a placeholder to indicate the absence of the content:

<xsl:template name="information">
    <xsl:param name="content">
    <xsl:choose>
        <xsl:when test="$content">
            <Content>
                <xsl:apply-templates select="$content/node()" />
            </Content>
        </xsl:when>
        <xsl:otherwise>
            <PlaceHolder/>
        </xsl:otherwise>
    </xsl:choose>
</xsl:template>

This works well, until content is a result tree fragment:

<xsl:call-template name="information">
    <xsl:with-param name="content">Yes</content>
</xsl:call-template>

I'm using the Microsoft .NET XSLT engine, so I can call msxsl:node-set() on a parameter to obtain a workable node-set, but I don't know how to test if the parameter needs this treatment. It is by far the lesser case that the content is generated.

Is there a way to make this template work for proper node-sets and result tree fragments?

Solution

  • XslCompiledTransform in .NET 2.0 and later supports exsl:object-type http://exslt.org/exsl/functions/object-type/index.html so you can check the type of your variable if needed. On the other hand I don't think there is a problem in calling msxsl:node-set on a node set instead of a result tree fragment, it simply returns the node set unchanged.