Seeking an explanation

Hello all,

I've figured out my problem, I just don't understand why and would appreciate
an explanation please.
I'm using XSLT v1

My XML (cut down but <det> may or may not be in the same parent node)
<det>
	<det_rep_group>10</det_rep_group>
	<det_format>test</det_format>
<det>
<det>
	<det_rep_group>10</det_rep_group>
	<det_format>live</det_format>
<det>
<det>
	<det_rep_group>20</det_rep_group>
	<det_format>live</det_format>
<det>

I wanted to get all <det> nodes, where <det_format> did not equal "test" and
then group them based on <det_rep_group>
My problem was Group 10 was being excluded when I expected it to be a valid
selection.

What I was doing:
<xsl:key name="g" match ="det/det_rep_group" use="."/>
.
.
<xsl:variable name="g"
select="//det[det_format!='test']/det_rep_group[generate-id()=generate-id(key
('g',.))]" />
<xsl:for-each select=$g">
.
.
</xsl:for-each>

What I am now doing:
<xsl:key name="g" match ="det[det_format!='test']/det_rep_group" use="."/>
.
.
<xsl:variable name="g"
select="//det/det_rep_group[generate-id()=generate-id(key('g',.))]" />

I understand the difference between det[not(det_format='test')] and
det[det_format!='test'], yet can't see the wood for the trees on this issue.
Thanks in advance for an explanation.

Carl Radley


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