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RE: [xsl] Extracting a list of unique base urls from anchors in a html docu ment.

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Hi David,

I adopted your earlier suggestion, and used a map:

<xsl:key name="local-links" match="a[contains(@href, '#') and
not(contains(@href, '/'))]" use="substring-before(@href,'#')"/>

The code that uses this map to extract information looks like:

Unique base-urls:
<xsl:for-each select="//a[generate-id() = generate-id(key('local-links',
substring-before(@href, '#'))[1])]">
	href base: <xsl:value-of select="substring-before(@href, '#')"/>
	occurances: <xsl:value-of select="count(key('local-links',
substring-before(@href, '#')))"/> 
</xsl:for-each>	

Can the code above be written in a more efficient way? I guess there isn't a
way to directly iterate over the keys in a map created by <xsl:key>?

By main question, however, is this: how can I aggregate this table of data
into an aggregated one, where every base url part maps to a count of
occurances of this base url part in the source document?


Thanks,
// tt

> -----Original Message-----
> From: David Carlisle [mailto:davidc@xxxxxxxxx]
> Sent: Thursday, September 13, 2001 8:06 PM
> To: xsl-list@xxxxxxxxxxxxxxxxxxxxxx
> Subject: Re: [xsl] Extracting a list of unique base urls from 
> anchors in
> a html docu ment.
> 
> 
> 
> > I'm propably wrong,
> 
> I'm afraid so:-)
> 
> > The only difference is that my template doesn't compare the 
> attribute values
> > as-is, but applies a substring before doing so.
> 
> No the string function completely changes the sematics of =.
> 
> If you have an XPath test of the form
> 
> (node-set a) = (node-set b)
> 
> then it is true if _any_ node in set a has a value equal to 
> any node in
> set b.
> 
> That's what you have here:
> 
> @country=preceding-sibling::city/@country
> 
> @country and preceding-sibling::city/@country
> both select node sets.
> 
> If you have
> 
> (string a) = (string b)
> 
> then this is true if the string a equals to the string b.
> 
> that's what you have here:
> 
> substring-before(@href,'#')=substring-before(preceding::a/@href,'#')
> 
> as substring-before always returns a string.
> 
> substring-before requires a string as its first argument and 
> if you give
> it a node set (as here) then it takes the string value of the 
> first node
> (in document order) of the node set.
> 
> @href has at most one node but preceding::a/@href has perhaps 
> many node but
> whatever the current node the first node in that collection 
> is the first
> href attribute on an a element that occurs in the document.
> 
> David
> 
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