How Do You Enter a URI in XSLT as an XPath Expression?

[honestrosewater]

This question is extremely annoying but not worth the time to properly investigate, so here is my best attempt to find an answer.

I'm writing something in XSLT and XPath (both 2.0). I want to declare a URI parameter.

<xsl:param name="foo" as="xsd:anyURI" select="http://foo.bar"/>[/indent]

But Saxon complains about that being a parse error (XPST0003: "QName cannot end with a colon {http:}"). So I thought maybe it wants me to enter the URI as a string. But no, that is also bad, a type error, as you would initially expect (XPTE0600). So what is a girl to do?

The value of select must be an XPath expression, but I cannot for the life of me figure out what kind of expression it is. It's not a quantified, conditional, for, comparison, arithmetic, or sequence expression. And of the primary expressions, the only one I can imagine it might be is a string literal, but that doesn't really even make sense. It's not a path expression, is it? URIs are atomic values, surely, right? xsd:anyURI is an atomic type. Bah.

I have solved this for now by just entering the URI as a string and casting it as a URI,

<xsl:param name="foo" as="xsd:anyURI" select="'http://foo.bar' cast as xsd:anyURI"/>​

but that is not satisfying.

How do you enter a URI in XSLT as an XPath expression?​

 

[Aaron Bex]

Unfortunately, there is no straightforward answer to this question. The best solution is likely to use the cast as xsd:anyURI expression as mentioned above, or if possible, to avoid declaring the URI as a parameter and instead to hardcode it into the XSLT.

 

[ravenprp]

According to the W3C XPath 2.0 specification, a URI can be entered as an XPath expression by using the "fn:uri" function, which takes a string as its argument and returns an xs:anyURI value. So in your case, the correct syntax would be:

<xsl:param name="foo" as="xsd:anyURI" select="fn:uri('http://foo.bar')"/>

This function can also be used to convert a string value to a URI, so your workaround of casting the string as a URI is not necessary. The correct syntax for that would be:

<xsl:param name="foo" as="xsd:anyURI" select="xs:anyURI('http://foo.bar')"/>

I hope this helps and resolves your issue. It's always important to consult the official documentation when encountering errors or issues in your code.