Re: [xsl] Help parsing a node

[Martin Honnen <Martin.Honnen@xxxxxx>]

Michele R Combs wrote:

> I didn't write this line of code -- it's in a style sheet I'm attempting to comprehend -- so I don't want to change anything until I understand what it's doing.  But more to the point, it actually is working 99% of the time.  There's just one single case where it's counting something as unique when it shouldn't and I have no idea why,, which is why I'm trying to understand precisely what it is selecting and how.  The line I cited:
>
> <xsl:variable name="uniqueTypes" select="ead/archdesc/dsc/descendant::*/container[not(@type=following::*/container/@type)]/@type" />
>
> appears at the very start of the style sheet, at which point yes, there is an element<ead>  and yes, it will find something. Hence my first question: what precisely is this selecting and how?  I *think* that it is selecting certain @type attributes from various<container>  elements but I'm not sure which ones, or how it knows that they're unique.
>
> The variable $uniqueTypes is then used later at various places in the code, for example:
>
> <xsl:for-each select="$uniqueTypes">
>
> Hence my second question, whether $uniqueTypes  is the same no matter where it gets used later.

A variable gets one value and that value never changes, even if the 
variable is used in different locations.

If the xsl:variable element is a child of the xsl:stylesheet element 
then it is a global variable and then I think a relative path is 
evaluated relative to the initial context node which is usually the root 
node (also called document node).

I don't see why you would get different results with the same variable 
used in different places unless there is local parameter or variable of 
the same name hiding the global one.

--

	Martin Honnen --- MVP Data Platform Development
	http://msmvps.com/blogs/martin_honnen/