How to access the document node if context item is an atomic value?

apollo13 · August 2nd, 2010, 07:51 AM

Hi,

I do have a snippet like this:

Code:

<xsl:for-each select="('option1', 'option2')">
  <xsl:value-of select="/root/to/some/element"/>
</xsl:for-each>

The, example per se is obviously pretty useless but perfectly illustrates my problem. The error I get is the following:

Code:

XPTY0020: Leading '/' cannot select the root node of the tree containing the context item: the context item is an atomic value

I do understand why this error occurs and what it's telling me but I don't know a way around it. I tried using a variable like this:

Code:

<xsl:variable name="helper" as="element()+">
  <item>option1</item><item>option2</item>
</xsl:variable>

Iterating over that variable instead of my atomic sequence did work, but accessing "/root/to/some/element" obviously failed:

Code:

net.sf.saxon.trans.XPathException: The root of the tree containing the context item is not a document node

(Yeah I assume the last try was pretty desperate ;))

Is there a way to access the document node in my loop?

Thanks in advance,
Florian

P.S.: The only way I found was putting / into a variable before entering the loop, but that's somewhat ugly imo.

Martin Honnen · August 2nd, 2010, 07:58 AM

Create a variable

Code:

<xsl:variable name="doc1" select="/"/>

outside of the for-each, then inside of the for-each you can access

Code:

<xsl:value-of select="$doc1/root/to/some/element"/>

With your current code you get the error as the context item (defined by the select expression of the for-each) is not a node so using a path expression like "/" does not make sense as it needs a context node, not an atomic value like a string.

apollo13 · August 2nd, 2010, 08:03 AM

Hi,

yeah that's what I am currently using (just updated the post, but you were faster ;)). But in my opinion using a variable here is somewhat ugly, so if there are other ways I am all ears.

Cheers,
Florian

Martin Honnen · August 2nd, 2010, 08:23 AM

An XPath like "/" needs a context node thus when you have a context item that is not a node you need a variable to store a reference to the document you want to access. The same problem can also occur in XSLT 1.0 when you process nodes from different documents, you need a variable too in that case. It might look ugly to you but I don't think there is solution that is shorter or more elegant.

apollo13 · August 2nd, 2010, 08:27 AM

Guess I'll live with it then ;) Thx for your answers.