Is there a way to match multiple modes in one template?

mphare · June 24th, 2011, 02:13 PM

I am using Saxon 9 on Windows 7/64 in a cygwin bash shell.

I have a chain of templates that process using a mode="import" on each template.
Somewhere near the end of the chain I would like to diverge the processing to a different template for certain cases. These cases are known at the start of the chain, so what I want to do is something like:

Code:

<xs:template match="A" mode="a | b">
  <xs:apply-templates select="B" mode="#current"/>
</>

<xs:template match="B" mode="a | b">
  <xs:apply-templates select="C" mode="#current"/>
</>

<!-- here I diverge -->

<xs:template match="C" mode="a">
   <xs:apply-templates select="D" mode="#current"/>
 </>
 
<xs:template match="C" mode="b">
   <xs:apply-templates select="E" mode="#current"/>
 </>

I know I have severely butchered the syntax in favour of brevity, but I hope you get the idea.

In reality my chain is much deeper than this. When I start I know if I want the D or the E behavour, so I can start out using the mode a or b and use the same templates up until I get to the end where a or b will select the D or E template path.

My other alternatives are to write parallel templates for a and for b, or to consider refactoring my code to do the processing a different way.

mhkay · June 24th, 2011, 06:01 PM

The mode attribute of xsl:template is a space-separated list of mode names.

I'm surprised that you found it difficult to find this information in the spec or in reference books.

mphare · June 28th, 2011, 02:52 PM

The spec doesn't indicate that a list was even possible. Section 5.7 just says the value of the modes must match and what happens if they do not.
Your book does indicate that a list is possible, but I didn't understand how the list items were delimited, hence my question here.

Thanks for the help!

samjudson · June 28th, 2011, 03:09 PM

The spec states: "... its value must be a non-empty whitespace-separated list of tokens, each of which defines a mode to which the template rule is applicable."

http://www.w3.org/TR/xslt20/#dt-mode

mphare · June 28th, 2011, 03:18 PM

Well, that's my problem - I'm looking at the 1.0 spec.

Thanks, for the heads up. Sam.

- m

djbpitt · November 8th, 2017, 07:39 AM

If I'm reading correctly, the description of the value of the @mode attribute for <xsl:apply-templates> in the fourth edition says "Lexical QName or Â«#currentÂ»". For what it's worth, I was confused by the singular QName as well, and I'm grateful for the clarification here.

djbpitt · November 9th, 2017, 11:49 AM

... which, of course, makes sense, since <xsl:apply-templates> can select only one mode at a time. I was looking in the wrong place in the book. Doh!