Hi,

I have a piece of XSLT which opens a set of documents
in a for-each block. However I don't know at the time
the script runs whether or not all the files exist.

Currently this isn't a problem because Saxon has recoverable
errors, where the processor continues onto the next iteration.
However MS XML Pack doesn't handle this and craps out.

Is there a way to check whether or not the document() has actually
found the file before continuing? I've tried:

<xs:if test="document()">
....

But this doesn't fail if the file is not present.

Cheers,

Nick

Any XSLT processor which conforms to the XSLT spec must deal with the document() function in this way if there is a problem with retrieving the XML document:
it may signal an error; if it doesn't, it must recover the error by returning an empty nodeset.
So, if, as you're saying, "this doesn't fail if the file is not present", then the function must return an empty nodeset, and you can simply test it by this:
Regards,
Armen

Hi

Unfortunately, MSXML uses XSLT 1.0 and it doesn't seem to be upgraded.

So my solution looks like this:
- new template "xml-file-exists" which opens VALID SERVICE_URL with file parameter. That URL returns VALID XML with root element and text node, saying "true" or false.
- use that template to generate variable and the pass variable to xsl:choose
- inside xsl:when at "true" use document()

The code
=======
  <xsl:template name="xml-file-exists">
    <xsl:param name="url"/>
    <xsl:variable name="test-url">http://SERVICE_URL?url=<xsl:value-of select="$url"/>
    </xsl:variable>
    <xsl:copy-of select="document($test-url)//file"/>
  </xsl:template>


  <xsl:variable name="file-exists">
    <xsl:call-template name="xml-file-exists">
      <xsl:with-param name="url" select="$options.xml"/>
    </xsl:call-template>
  </xsl:variable>

  <xsl:choose>
     <xsl:when test="$file-exists='true'">
     ...xsl code using document()...
     </xsl:when>
     <xsl:otherwise>
     ...xsl code without document()
     </xsl:otherwise>
  </xsl:choose>