Remove duplicate elements based on attributes and values - xslt

Question

There are many questions about how to remove duplicate elements when you can group those elements by a certain attribute or value, however, in my case the attributes are being dynamically generated in the XSLT already and I don't want to have to program in every attribute for every element to use as a grouping key.
How do you remove duplicate elements without knowing in advance their attributes? So far, I've tried using generate-id() on each element and grouping by that, but the problem is generate-id isn't generating the same ID for elements with the same attributes:
<xsl:template match="root">
<xsl:variable name="tempIds">
<xsl:for-each select="./*>
<xsl:copy>
<xsl:copy-of select="#*"/>
<xsl:attribute name="tempID">
<xsl:value-of select="generate-id(.)"/>
</xsl:attribute>
<xsl:copy-of select="node()"/>
</xsl:copy>
</xsl:for-each>
</xsl:variable>
<xsl:for-each-group select="$tempIds" group-by="#tempID">
<xsl:sequence select="."/>
</xsl:for-each-group>
</xsl:template>
Test data:
<root>
<child1>
<etc/>
</child1>
<dynamicElement1 a="2" b="3"/>
<dynamicElement2 c="3" d="4"/>
<dynamicElement2 c="3" d="5"/>
<dynamicElement1 a="2" b="3"/>
</root>
With the end result being only one of the two dynamicElement1 elements remaining:
<root>
<child1>
<etc/>
</child1>
<dynamicElement1 a="2" b="3"/>
<dynamicElement2 c="3" d="4"/>
<dynamicElement2 c="3" d="5"/>
</root>

Answer 1

In XSLT 3 as shown in https://xsltfiddle.liberty-development.net/pPqsHTi you can use a composite key of all attributes with e.g.
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
version="3.0">
<xsl:mode on-no-match="shallow-copy"/>
<xsl:output indent="yes"/>
<xsl:template match="root">
<xsl:copy>
<xsl:for-each-group select="*" composite="yes" group-by="#*">
<xsl:sequence select="."/>
</xsl:for-each-group>
</xsl:copy>
</xsl:template>
</xsl:stylesheet>
Note that technically attributes are not ordered so it might be safer to group by a sort of the attributes by node-name() or similar, as done with XSLT 3 without higher-order functions in https://xsltfiddle.liberty-development.net/pPqsHTi/2
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:mf="http://example.com/mf"
version="3.0">
<xsl:mode on-no-match="shallow-copy"/>
<xsl:output indent="yes"/>
<xsl:function name="mf:node-sort" as="node()*">
<xsl:param name="input-nodes" as="node()*"/>
<xsl:perform-sort select="$input-nodes">
<xsl:sort select="namespace-uri()"/>
<xsl:sort select="local-name()"/>
</xsl:perform-sort>
</xsl:function>
<xsl:template match="root">
<xsl:copy>
<xsl:for-each-group select="*" composite="yes" group-by="mf:node-sort(#*)">
<xsl:sequence select="."/>
</xsl:for-each-group>
</xsl:copy>
</xsl:template>
</xsl:stylesheet>
or as you could do with Saxon EE simply with
<xsl:template match="root">
<xsl:copy>
<xsl:for-each-group select="*" composite="yes" group-by="sort(#*, (), function($att) { namespace-uri($att), local-name($att) })">
<xsl:sequence select="."/>
</xsl:for-each-group>
</xsl:copy>
</xsl:template>

Answer 2

<xsl:template match="#*|node()">
<xsl:copy>
<xsl:apply-templates select="#*|node()"/>
</xsl:copy>
</xsl:template>
<xsl:template match="root/*[#a= following-sibling::*/#a]|root/*[#c= following-sibling::*/#c and #d= following-sibling::*/#d]"/>
You may try this