RE: Evaluating XML inside attributes (using XSLT 2.0 a

We more usually see this problem in the form of escaped markup inside CDATA
sections, but essentially it's the same problem and the same solution (and
the same note of censure that whoever designed this XML should be shot at
dawn). Because the markup has been escaped, it escapes the attention of the
XML parser the first time through. You have to extract the attribute value
as a string, and then pass it to an XML parser for re-parsing. You can't do
that in standard XSLT, but you can do it by calling the saxon:parse()
extension function. You'll have to wrap it in an element to make it
well-formed: so you will want something like

saxon:parse(concat("<wrapper>", @title, "</wrapper>" ))

Regards,

Michael Kay
http://www.saxonica.com/
http://twitter.com/michaelhkay 

> -----Original Message-----
> From: Jacobus Reyneke [mailto:jacobusreyneke@xxxxxxxxx] 
> Sent: 24 March 2010 18:39
> To: xsl-list@xxxxxxxxxxxxxxxxxxxxxx
> Subject:  Evaluating XML inside attributes (using XSLT 
> 2.0 and Saxon)
> 
> Good day,
> 
> This is in relation to my earlier posts, but I have not yet 
> been able to solve my problem. I have tried working around 
> the problem below, but because of the type of information I'm 
> working with (labeling and vector graphics), I can't get past 
> the fact that sometimes I end up with attributes that will 
> get part of their content from other parts of the XML document.
> 
> Can anyone please share some ideas around evaluating 
> information for use inside xml attributes. I know it's ugly, 
> horrible and terrible to escape XML an dump it inside an 
> attribute, but I need to reference content by id from inside 
> attributes from time to time. I can move attributes out into 
> child elements, but this can become even more confusing.
> 
> Input:
> <root>
>   <name lookup-id="5">
>     Johny
>   </information>
>   <chapter title="The life of &lt;x&gt;5&lt;/x&gt;">
>      Everyone knew that <x>5</x> was a happy child
>   </chapter>
> </root>
> 
> XSLT
> ???
> 
> Required output:
> <root>
>   <name lookup-id="5">Johny</information>
>   <chapter title="The life of Johny">Everyone knew that Johny 
> was a happy child</chapter> </root>
> 
> I'm unable to get the XSLT processor to evaluate the content 
> of the title attribute. Obviously a template matching x does 
> not get called for content inside attributes.
> 
> A generic approach would be ideal. Something that will work 
> no matter where <x>5</x> is.
> 
> Kind regards,
> Jacobus