Re: [xsl] Help parsing a node

[Michael Kay <mike@xxxxxxxxxxxx>]

On 26/04/2012 16:51, Michele R Combs wrote:
> Hi all --
>
> Can someone translate this into plain English for me?
>
> <xsl:variable name="uniqueTypes" select="ead/archdesc/dsc/descendant::*/container[not(@type=following::*/container/@type)]/@type" />
Roughly, it selects all the @type attributes provided there is no @type 
attribute later in the document with the same value.

And it does this very inefficiently (n*2 performance where n is the 
document size) - it can be done much more efficiently using keys.

It also doesn't do quite what I said. Assuming it's used with "/" as the 
context item, It's actually looking for all @type attributes whose path 
is /ead/archdesc/dsc//container, provided they aren't the same as a 
following @type attribute whose path is //container. If there are @type 
attributes that match the first path and not the second, that could lead 
to some strange effects.

It could even select duplicates. If there happens to be a structure like 
this:

<container type="x">
<container type="x"/>
</container>

then both type attributes will be selected, because the second is not 
"following" the first.

Michael Kay
Saxonica
> What exactly will this select?  And (since it starts with the root node) will it select the exact same thing no matter where it's used?
>
> I thought I knew but it isn't behaving at all the way I expected.
>
> Thanks --
>
> Michele
> +++++++++++++++
> Michele Combs
> Lead Archivist
> Special Collections Research Center
> Syracuse University
> 315-443-2081
> mrrothen@xxxxxxx
> scrc.syr.edu
> library-blog.syr.edu/scrc