Re: AW: [xsl] simple conditional looping

[Wendell Piez <wapiez@xxxxxxxxxxxxxxxx>]

At 07:19 AM 8/16/2004, David wrote:
> > maybe a silly question, but why exactly do you need the ()? something
> > like //* with a predicate [] should be enough or not?
>
> A predicate in an axis step just filters that step.
>
> //*[position() < 50]
>
> is /descendent-or-self::node/child::*[position() < 50]
>
> so it gives you all element nodes in the document that have fewer than
> 49 older siblings.
>
> On the other hand
>
> (//*)[position() < 50]
>
>
> is (/descendent-or-self::node/child::*)[position() < 50]
>
> which gives you the first 49 element nodes in the document.

Another (simple) way to do it is

/descendant::*[position() < 50]

...which may be less confusing for those not schooled in the arcana of 
XPath short syntax (but who use it anyway).

Note these are solutions to "iterating X times", but often in XSLT you only 
need to do this because you want to group a given set of nodes into batches 
of X, in which case the "Piez method" (iterating over an arbitrary set of 
nodes that happens to be large enough) is not only sneaky (and maybe ugly), 
it's gratuitous.

Cheers,
Wendell



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Wendell Piez                            mailto:wapiez@xxxxxxxxxxxxxxxx
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