Re: Empty String param

On Wed, Apr 02 2008 15:21:25 +0100, richard.kerry@xxxxxxxxxxx wrote:
...
> <xsl:template name="insert">
> <xsl:param name="default" />
> <!-- various stuff using $default-->
> </xsl:template>
>  
> And eventually I do 
> <xsl:call-template name="insert">
> <xsl:with-param name="default" select="$named-nodes[1]/@default" />
> </xsl:call-template>
>  
> So that I can get the value of default from an atribute in another
> document ($named-nodes).
> This attribute may be, and often is, absent.  In which case I'd expect
> default to be an empty string. Which it is for this test.
>  
>  
> I get an error as follows :
> XTTE0570: An empty sequence is not allowed as the value of parameter
> $default.
> Referring to the xsl:with-param line.
>  
> Why can't I pass in the empty string here ?
> (ie why is it telling me that an empty sequence (should be a string) is
> not allowed ?)

I had trouble replicating your error message.

Are you using tunnel parameters?  I was able to induce error XTTE0590
(which is a more correct error code for this fault, irrespective of
whether the fault is real or imagined) with Saxon 9.0.0.4 by using
tunnel parameters.

The following stylesheet runs without error, but will fail with XTTE0590
if you uncomment the xsl:call-template to the 'intermediate' template.

------------------------------------------------------------
<?xml version="1.0" encoding="utf-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
                version="2.0">

  <xsl:output method="xml"/>

  <xsl:variable name="named-nodes" as="element()*">
    <node1 default1="a"/>
  </xsl:variable>

  <xsl:template name="insert">
    <xsl:param name="default" />
    <!-- various stuff using $default-->
    <xsl:value-of select="$default"/>
  </xsl:template>

  <xsl:template name="intermediate">
    <xsl:param name="default" tunnel="yes" as="attribute()"/>
    <xsl:call-template name="insert">
      <xsl:with-param name="default" select="$named-nodes[1]/@default" />
    </xsl:call-template>
  </xsl:template>

  <xsl:template match="/">
    <xsl:call-template name="insert"/>
    <!--<xsl:call-template name="intermediate">
      <xsl:with-param name="default"
        select="$named-nodes[1]/@default"
        tunnel="yes" />
    </xsl:call-template>-->
  </xsl:template>

</xsl:stylesheet>
------------------------------------------------------------

Regards,


Tony Graham                         Tony.Graham@xxxxxxxxxxxxxxxxxxxxxx
Director                                  W3C XSL FO SG Invited Expert
Menteith Consulting Ltd
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