In some cases I force Saxon to use a template or variable by directing it
to output something that I know can never exist such as
<xsl:copy-of
select="foobar"/>
I know there is no <foobar> node but Saxon
does not know that at compile time so it does include the template and execute
it.
Mike told me that the later Saxon optimizers will completely
eliminate a template that does not appear to produce an output in a static
evaluation. That optimizer cannot know that <foobar> does not exist so
it spares that template's life. At least that's the way I understand
it.
HTH,
Roger Kovack
I'm
not quite sure how this is supposed to relate to the original
problem.
There are cases where you have to "fool" Saxon into executing code that
it might otherwise optimize out: the usual case is where you have an extension
function with side-effects. If you call this using
<xsl:variable name="x"
select="my:extension(123)"/>
and
never reference $x, the variable will not be evaluated. If
the method underpinning the extension function returns void, you can
get round this by using <xsl:sequence select="my:extension(123)"/> -
Saxon assumes that if you are calling a method that returns void, you are
probably doing so for a reason.
Michael Kay
http://www.saxonica.com/
