Re: [xsl] XSLT 2.0 *and* XSLT 1.0 validation -- how to?

[Dimtre Novatchev <dnovatchev@xxxxxxxxx>]

Hi Jeni,


On Sun, 24 Oct 2004 11:03:02 +0100, Jeni Tennison <jeni@xxxxxxxxxxxxxxxx> wrote:
> Hi Dimitre,
> 
> 
> 
> > My question was, could there be a single schema that has both the
> > rules for XSLT 1.0 and the rules for XSLT 2.0 and that, dependent on
> > the value of the "version" attribute of an instance behaves exactly
> > as an XSLT 1.0 schema only or exactly as an XSLT 2.0 schema only.
> >
> > I can imagine doing this with a pre-processor, which only reads and
> > analyzes the xsl:stylesheet instruction, then depending on the
> > version attribute it validates with only one of two schemas. Or, if
> > rules in the schema can be based on a condition, it will set the
> > condition to true or false and then validate with a single combined
> > schema passing to it (e.g. setting this in DOM) the value of this
> > condition.
> >
> > Can this be done?
> 
> The trouble is that XSLT allows regions of a stylesheet to belong to
> different versions. In XSLT 1.0, you can put an xsl:version attribute
> on any literal result element to indicate the version of XSLT used in
> the content of that element. In XSLT 2.0, any XSLT element can have a
> version attribute, and any other element can have a xsl:version
> attribute that does the same thing.

Oh, I didn't know that... My first reaction is to wonder if such a
feature can be really useful.

> 
> So it's not as simple as looking at the version attribute on the
> <xsl:stylesheet> element and choosing which version of the schema to
> use based on that.
> 
> I think you could probably write a RELAX NG schema that used the
> version switch correctly, wherever it was used (since RELAX NG
> supports co-occurrence constraints, unlike XML Schema); I haven't
> looked at Norm's, so I don't know whether his does that.
> 
> Personally, I don't think that it's worth validating XSLT stylesheets
> against a schema. It's simpler, quicker, more accurate and more
> helpful to get an XSLT processor to check your stylesheet instead.

I also thought so in the past, but one can quickly get a powerful
language construction/editing environment --  by simply providing a
schema to an intelligent editor one can get correct
structure/intellisense support. And this is an example of really good
use of schemas.

Cheers,

Dimitre.