Re: [xsl] Wah? Weird... Clarifying the Schema

Subject: Re: [xsl] Wah? Weird... Clarifying the Schema
From: "M. David Peterson" <m.david@xxxxxxxxxx>
Date: Wed, 27 Oct 2004 22:05:56 -0700
Why wouldnt it work? All you are telling the processor to do is sort the result-set of the for-each loop. The resulting sort and the process of the original node-set being processes are two seperate processes and should not be confused by the fact that the sort element comes before the processing logic of the for-each loop. The sort element MUST be the first child (you can have multiple sort elements but they must follow each other sequentially w/o any other elements between the first and last sort element.) of for-each or apply-templates. Would be kind of a drag if that then meant that the elements were sorted first and then processed as such. Think:

sort = output in sorted order
and
for-each = processing in document order

And it might help things seem a little more clear.

Hope this helps!

<M:D/>

Michael wrote:

I've come across the strangest thing, and I'm trying to figure out why it occurs. I was hoping someone would enlighten me onto what is going on here:

I'm a recent member to the XSLT scene, so don't completely understand how the schema works to a full extend (i'm learning... slowly (grin)). Anyway, recently i've been playing around with some code that increments through each book in a catalog, and displays each book category from the catalog in a drop down box. To do this I decided to sort the catalog, incrementally go through each book node, then call a conditional statement that would only fire off if the previous node had a category that was different.

The weirdest thing happens here. Firstly, it has come to my attention that the 'preceding-sibling' axis is not effected by an 'xsl:sort' element. This is proved when removing the 'xsl:sort' element completely. The weird thing is that the code WORKS!!! So, i'm hoping I can get some clarification on this....

Why is the code working?

<xsl:for-each select="catalog/book">
<xsl:sort select="category" data-type="text" order="ascending" />
<xsl:if test="not(preceding-sibling::book/category = category)">
<xsl:choose>
<xsl:when test="category = $category">
<option value="{category}" selected="true"><xsl:value-of select="category" /></option>
</xsl:when>
<xsl:otherwise>
<option value="{category}"><xsl:value-of select="category" /></option>
</xsl:otherwise>
</xsl:choose>
</xsl:if>
</xsl:for-each>

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