[xsl] xsl:import and use-when

["Rushforth, Peter peter.rushforth@xxxxxxxxxxxxxxxxx" <xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx>]

Hi,

I have been experimenting with xsl:import@use-when to override templates
imported by the main stylesheet module with
an import@href value (partially) generated by a filtered maven variable.
Because the file so referenced may or may not exist, I've tried
to apply the @use-when attribute as follows:

  <xsl:import href="feedOrEntry2json-default.xsl"/>
  <xsl:import href="feedOrEntry2json-api.xsl"
use-when="doc-available('feedOrEntry2json-api.xsl')"/>

The string 'api' is generated by the filtered maven  variable, and the file
does exist in the same directory as the importing stylesheet
(when I execute the doc-available('feedOrEntry2json-api.xsl') call in the
xpath tester in oxygen, I get 'true' as a result).

However, when I execute the stylesheet, the templates in the first import are
(incorrectly) not overridden.
If I remove the @use-when, they are (correctly) overridden, but of course I
can't do that in general because sometimes the file won't
exist and in that case I don't want the compilation to fail, hence the
@use-when.

Any advice appreciated, with thanks.

Peter Rushforth