Re: [xsl] Things that make you go Hmmmm!

[David Carlisle <davidc@xxxxxxxxx>]

On 29/03/2014 12:42, Ihe Onwuka wrote:
> On Sat, Mar 29, 2014 at 11:57 AM, Andrew Welch <andrew.j.welch@xxxxxxxxx> wrote:
> > > On Fri, Mar 28, 2014 at 4:48 PM, Andrew Welch <andrew.j.welch@xxxxxxxxx> wrote:
> > > > > I was surprised that the content models of xsl:copy and xsl:copy-of
> > > > > were different (by dint of the select attribute) in the first place.
> > > >
> > > > They are still different, no? shallow vs deep.
> >
> > On 28 March 2014 17:50, Ihe Onwuka <ihe.onwuka@xxxxxxxxx> wrote:
> > > I'm not sure what point you are making.
> >
> > That the content models are still different (not just the select attribute).
>
> The only other difference I see is that xsl:copy has a
> use-attribute-set attribute and the xsl:copy-of  doesn't.

But xsl:copy takes content, and xsl:copy-of is an empty element (as has 
been stated several times before) Why do you consider their content 
models remotely similar?


> I'd make them the same.

Why? and in what way, what would element content of xsl:copy-of do??

> > > As to my point. For the same reasons I would expect the content models
> > > of xsl:next-match, xsl:apply-templates and xsl:apply-imports to be the
> > > same.
> >
> > What would the xsl:sort child of xsl:next-match or xsl:apply-imports do?
>
> What does xsl:value-of a null string do?

It generates a text node with value a an empty string. In most 
circumstances that text node is then discarded when adding nodes to a 
parent node.


> What is the advantage  of restricting a language constructs content
> model to the use-cases you can foresee today. What is the disadvantage
> of doing that?

If you allow things you (or at least the language designer) has to say 
what they mean. What would you want element content of xsl:copy-of to mean?

David