Wrap node inside xslt element based on condition - xslt

I have to wrap certain nodes inside another element conditionally. In the below example I need to wrap CityName inside MyCity if city is Venezia. I have achieved it now, but i think there is better way of writing this without repeating the node. One way is to create a template and call that for the CityName, but is there any more elegant ways with fewer lines of code?
Input
<cities>
<city name="Milano"/>
<city name="Paris"/>
<city name="Munchen"/>
<city name="Lyon"/>
<city name="Venezia"/>
</cities>
My Xslt
<xsl:stylesheet version="2.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:template match="city">
<xsl:choose>
<xsl:when test="#name='Venezia'">
<myCity>
<CityName>
<xsl:value-of select="#name"/>
</CityName>
</myCity>
</xsl:when>
<xsl:otherwise>
<CityName>
<xsl:value-of select="#name"/>
</CityName>
</xsl:otherwise>
</xsl:choose>
</xsl:template>
<!-- Identity Transform-->
<xsl:template match="node()">
<xsl:copy>
<xsl:apply-templates select="node()"/>
</xsl:copy>
</xsl:template>
<xsl:template match="#*"/>
</xsl:stylesheet>
Output I am looking for
<cities>
<CityName>Milano</CityName>
<CityName>Paris</CityName>
<CityName>Munchen</CityName>
<CityName>Lyon</CityName>
<myCity>
<CityName>Venezia</CityName>
</myCity>
</cities>

I think that all you need is:
<xsl:stylesheet version="2.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:template match="city[#name='Venezia']">
<myCity>
<xsl:next-match/>
</myCity>
</xsl:template>
<xsl:template match="city">
<CityName>
<xsl:value-of select="#name"/>
</CityName>
</xsl:template>
<!-- Identity Transform-->
<xsl:template match="node()">
<xsl:copy>
<xsl:apply-templates select="node()"/>
</xsl:copy>
</xsl:template>
</xsl:stylesheet>

With XSLT 3 it boils down to
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
version="3.0"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
exclude-result-prefixes="#all"
expand-text="yes">
<xsl:template match="city[#name]">
<CityName>{#name}</CityName>
</xsl:template>
<xsl:template match="city[#name = 'Venezia']">
<myCity>
<xsl:next-match/>
</myCity>
</xsl:template>
<xsl:mode on-no-match="shallow-copy" on-multiple-match="use-last"/>
</xsl:stylesheet>
xsl:next-match is also available in XSLT 2.0 but you would need to specify priority on a template instead of relying on xsl:mode on-multiple-match="use-last". Text value templates in XSLT 3 are just syntactic sugar that can be replace with xsl:value-of.

Related

Predicates vs recursive templates vs other

consider this simple problem:
we wish to map this input to the same output except the first occurence of a 'foo' element with "#bar = '1'", we add a new attribute #wibble, so this:
<root>
<foo/>
<foo/>
<foo/>
<foo bar="1"/>
<foo bar="1"/>
<foo/>
<foo/>
<foo/>
<foo/>
<foo/>
</root>
goes to this:
<root>
<foo />
<foo />
<foo />
<foo wibble="2" bar="1" />
<foo bar="1" />
<foo />
<foo />
<foo />
<foo />
<foo />
</root>
I could implement this mapping using the identity pattern (not sure what this pattern is called), but it would go like this:
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:msxsl="urn:schemas-microsoft-com:xslt" exclude-result-prefixes="msxsl"
>
<xsl:output method="xml" indent="yes"/>
<xsl:template match="/">
<xsl:apply-templates select="root" mode="findFirst"/>
</xsl:template>
<xsl:template match="#* | node()" mode="findFirst">
<xsl:copy>
<xsl:apply-templates select="#* | node()" mode="findFirst"/>
</xsl:copy>
</xsl:template>
<xsl:template match="foo[#bar='1'][1]" mode="findFirst">
<xsl:copy>
<xsl:attribute name="wibble">2</xsl:attribute>
<xsl:apply-templates select="#* | node()" mode="findFirst"/>
</xsl:copy>
</xsl:template>
</xsl:stylesheet>
i.e. we override the identity template with some match statement which matches the specific scenario we want to match, implement our overriding mapping, and then continue.
I use this style a lot.
Sometimes though the match statement is complex (we saw this in another question recently about mapping lines of code). I find these sort of matches problematic, in the above scenario the use case is simple, but sometimes the logic isnt easily (or at all) expressibly inside the match statement, in which case I'm tempted to fall back on recursive functional patterns, and in this case I'd write a recursive template like this.
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:msxsl="urn:schemas-microsoft-com:xslt" exclude-result-prefixes="msxsl"
>
<xsl:output method="xml" indent="yes"/>
<xsl:template match="/">
<root>
<xsl:apply-templates select="root/foo[1]" mode="findFirst">
<xsl:with-param name="isFound" select="false()"/>
</xsl:apply-templates>
</root>
</xsl:template>
<xsl:template match="foo" mode="findFirst">
<xsl:param name="isFound"/>
<xsl:copy>
<xsl:if test="$isFound = false() and #bar = '1'">
<xsl:attribute name="wibble">2</xsl:attribute>
</xsl:if>
<xsl:apply-templates select="#* | node()" mode="identity"/>
</xsl:copy>
<xsl:choose>
<xsl:when test="$isFound = false() and #bar = '1'">
<xsl:apply-templates select="following-sibling::foo[1]" mode="findFirst">
<xsl:with-param name="isFound" select="true()"/>
</xsl:apply-templates>
</xsl:when>
<xsl:otherwise>
<xsl:apply-templates select="following-sibling::foo[1]" mode="findFirst">
<xsl:with-param name="isFound" select="$isFound"/>
</xsl:apply-templates>
</xsl:otherwise>
</xsl:choose>
</xsl:template>
<xsl:template match="#* | node()" mode="identity">
<xsl:copy>
<xsl:apply-templates select="#* | node()" mode="identity"/>
</xsl:copy>
</xsl:template>
</xsl:stylesheet>
this basically treats the nodeset as a functional 'list', taking the head (and passing the tail implicitly).
Now we can implement much more complex logic and use parameters to pass the current state of the (effectively fold) through the recursion, but at the cost of extra complexity.
BUT....
Is this style of programming sustainable in XSLT? - I always worry about stack overflow (ironically!), due to probable non tail recursion in the XSLT engine of the recursive template.
My knowledge of XSLT 3.0 is extremely limited (any references to good learning resources always appreciated), but in a FP language the alternative to direct recursion would be to use fold, where fold is written as a tail recursive function, and fold IS available in XSLT 3.0, but is this a sensible alternative?
are there other patterns of usage that I can use?
XSLT has xsl:iterate (https://www.w3.org/TR/xslt-30/#iterate) which allows you to implement your sibling recursion in a declarative way that looks a bit like a loop and due to its structure and implementation avoids any stack overflow recursion; iterate example:
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
version="3.0"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
exclude-result-prefixes="#all"
expand-text="yes">
<xsl:template match="/*">
<xsl:copy>
<xsl:apply-templates select="#*"/>
<xsl:iterate select="node()">
<xsl:param name="found" select="false()"/>
<xsl:variable name="is-first-foo" select="if (. instance of element(foo)) then not($found) and boolean(self::foo[#bar = 1]) else $found"/>
<xsl:choose>
<xsl:when test="$is-first-foo">
<xsl:copy>
<xsl:attribute name="wibble" select="2"/>
<xsl:apply-templates select="#*"/>
<xsl:apply-templates/>
</xsl:copy>
</xsl:when>
<xsl:otherwise>
<xsl:apply-templates select="."/>
</xsl:otherwise>
</xsl:choose>
<xsl:next-iteration>
<xsl:with-param name="found" select="$is-first-foo"/>
</xsl:next-iteration>
</xsl:iterate>
</xsl:copy>
</xsl:template>
<xsl:mode on-no-match="shallow-copy"/>
</xsl:stylesheet>
fold-left is certainly also available at the XPath 3.1 level, integrating it with the XML syntax of XSLT (3.0) is a bit more convoluted than in XQuery 3.1 where basically all is an expression. But is is certainly an option; example online:
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
version="3.0"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
exclude-result-prefixes="#all"
xmlns:mf="http://example.com/mf"
expand-text="yes">
<xsl:function name="mf:add-attribute" as="element()">
<xsl:param name="element" as="element()"/>
<xsl:copy select="$element">
<xsl:attribute name="wibble" select="2"/>
<xsl:apply-templates select="#*"/>
<xsl:apply-templates/>
</xsl:copy>
</xsl:function>
<xsl:template match="/*">
<xsl:copy>
<xsl:apply-templates select="#*"/>
<xsl:sequence
select="fold-left(
node(),
map { 'found-foos' : 0, 'nodes' : () },
function($a, $n) {
let $is-foo := $n instance of element(foo) and boolean($n/self::foo[#bar = 1]),
$is-first-foo := $a?found-foos = 0 and $is-foo
return
map {
'found-foos' : if ($is-foo) then $a?found-foos + 1 else $a?found-foos,
'nodes': ($a?nodes, if ($is-first-foo) then mf:add-attribute($n) else $n)
}
}
)?nodes"/>
</xsl:copy>
</xsl:template>
<xsl:mode on-no-match="shallow-copy"/>
</xsl:stylesheet>
And for your sample an accumulator might allow you to check your conditions in a declarative way and then use its value in your match pattern to check whether you need to add your attribute. Online sample of accumulator use:
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
version="3.0"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
exclude-result-prefixes="#all"
expand-text="yes">
<xsl:param name="pattern" static="yes" as="xs:string" select="'foo[#bar = 1][1]'"/>
<xsl:accumulator name="have-first-foo-bar" as="xs:boolean" initial-value="false()">
<xsl:accumulator-rule _match="{$pattern}" select="true()"/>
<xsl:accumulator-rule phase="end" _match="{$pattern}" select="false()"/>
</xsl:accumulator>
<xsl:template match="foo[accumulator-before('have-first-foo-bar')]">
<xsl:copy>
<xsl:attribute name="wibble" select="2"/>
<xsl:apply-templates select="#*"/>
<xsl:apply-templates/>
</xsl:copy>
</xsl:template>
<xsl:mode on-no-match="shallow-copy" use-accumulators="#all"/>
</xsl:stylesheet>
A pattern I sometimes use for this is a global variable combined with a template rule:
<xsl:variable name="special-nodes" select="//foo[#bar='1'][1]"/>
<xsl:template match="$special-nodes">...</xsl:template>
It only works, of course, in a "single document" scenario where the global variable applies to the same document that you're processing with the template rule.

XMLT : replace values with values found in another xml

I have a file called ori.xml:
<?xml version="1.0" encoding="UTF-8"?>
<root>
<container>
<elA>
<el1>value1</el1>
<el2>value2</el2>
</elA>
<elB>
<el3>value3</el3>
<el4>value4</el4>
<el5>value5</el5>
</elB>
<elC>
<el6>value5</el6>
</elC>
</container>
</root>
and another one called modifs.xml:
<?xml version="1.0" encoding="UTF-8"?>
<els>
<el2>newvalue2</el2>
<el5>newvalue5</el5>
</els>
and I would like to obtain result.xml:
<?xml version="1.0" encoding="UTF-8"?>
<root>
<container>
<elA>
<el1>value1</el1>
<el2>newvalue2</el2>
</elA>
<elB>
<el3>value3</el3>
<el4>value4</el4>
<el5>newvalue5</el5>
</elB>
<elC>
<el6>value5</el6>
</elC>
</container>
</root>
I'm a beginner in XSLT.
So I started to write a stylesheet with which I'm able to change value2 into newvalue2:
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="xml" indent="yes"/>
<xsl:param name="fileName" select="'modifs.xml'" />
<xsl:param name="modifs" select="document($fileName)" />
<xsl:param name="updateEl" >
<xsl:value-of select="$modifs/els/el2" />
</xsl:param>
<xsl:template match="#* | node()">
<xsl:copy>
<xsl:apply-templates select="#* | node()"/>
</xsl:copy>
</xsl:template>
<xsl:template match="//elA/el2">
<xsl:copy>
<xsl:apply-templates select="$updateEl" />
</xsl:copy>
</xsl:template>
</xsl:stylesheet>
But now I have to modify this stylesheet to be able to know which elements are in modifs.xml and find them in ori.xml. I don't know how to do that. Could you help please ?
I would use a key:
<xsl:key name="ref-change" match="els/*" use="local-name()"/>
<xsl:template match="*[key('ref-change', local-name(), $modifs)]">
<xsl:copy-of select="key('ref-change', local-name(), $modifs)"/>
</xsl:template>
However, using the third argument for the key function is only supported in XSLT 2 and later thus if you use an XSLT 1 processor you need to move the logic into the template, that requires using for-each to "switch" the context document
<xsl:template match="*">
<xsl:variable name="this" select="."/>
<xsl:for-each select="$modifs">
<xsl:choose>
<xsl:when test="key('ref-change', local-name($this))">
<xsl:copy-of select="key('ref-change', local-name($this))"/>
</xsl:when>
<xsl:otherwise>
<xsl:for-each select="$this">
<xsl:call-template name="identity"/>
</xsl:for-each>
</xsl:otherwise>
</xsl:choose>
</xsl:for-each>
</xsl:template>
Put name="identity" on your identity transformation template.

Flattening with XSLT: I want to move one kind element one level

I have a XML file where elements B are inside elements A and I want to move them up. From:
<?xml version="1.0" encoding="utf-8"?>
<root>
<A>
<C>Text</C>
Text again
More text
<D>Other text</D>
<B>Text again</B>
<C>No</C>
<D>May be</D>
<B>What?</B>
</A>
<A>
Something
<B>Nothing</B>
<D>Again</D>
<B>Content</B>
End
</A>
</root>
I would like to have:
<?xml version="1.0" encoding="utf-8"?>
<root>
<A>
<C>Text</C>
Text again
More text
<D>Other text</D>
</A>
<B>Text again</B>
<A>
<C>No</C>
<D>May be</D>
</A>
<B>What?</B>
<A>
Something
</A>
<B>Nothing</B>
<A>
<D>Again</D>
</A>
<B>Content</B>
<A>
End
</A>
</root>
The closest XSLT program I have is this:
<xsl:stylesheet
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
exclude-result-prefixes="xs" version="1.0">
<xsl:output method="xml" indent="yes"/>
<xsl:template match="#* | node()">
<xsl:copy>
<xsl:apply-templates select="#* | node()"/>
</xsl:copy>
</xsl:template>
<xsl:template match="A">
<xsl:for-each select="*">
<xsl:choose>
<xsl:when test="name()='B'">
<xsl:apply-templates select="."/>
</xsl:when>
<xsl:otherwise>
<xsl:element name="A">
<xsl:apply-templates select="."/>
</xsl:element>
</xsl:otherwise>
</xsl:choose>
</xsl:for-each>
</xsl:template>
</xsl:stylesheet>
It has two problems: it ignores text nodes (this is probably just a matter of adding |text() to the select="*") but, more important, it creates a element for each node while I would like them to stay together under one . For instance, the above stylesheet makes:
<A><C>No</C></A>
<A><D>May be</D></A>
where I want:
<A><C>No</C>
<D>May be</D></A>
In my XML files, are always direct children of , and there is no or nesting.
The main use case is producing HTML where UL and OL cannot be inside a P.
This question is related but not identical to xslt flattening out child elements in a DocBook para element (and may be also to Flatten xml hierarchy using XSLT
)
As I said in the comment to your question, this is not about moving elements up in hierarchy. It is about grouping nodes, and creating a new parent A element for each group determined by the dividing B element.
In XSLT 1.0 this can be achieved using a so-called sibling recursion:
XSLT 1.0
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="xml" version="1.0" encoding="UTF-8" indent="yes"/>
<xsl:template match="/root">
<xsl:copy>
<xsl:apply-templates select="A"/>
</xsl:copy>
</xsl:template>
<xsl:template match="A">
<xsl:copy>
<xsl:apply-templates select="node()[1][not(self::B)]" mode="sibling"/>
</xsl:copy>
<xsl:apply-templates select="B[1]" mode="sibling"/>
</xsl:template>
<xsl:template match="node()" mode="sibling">
<xsl:copy-of select="." />
<xsl:apply-templates select="following-sibling::node()[1][not(self::B)]" mode="sibling"/>
</xsl:template>
<xsl:template match="B" mode="sibling">
<xsl:copy-of select="." />
<xsl:if test="following-sibling::node()[normalize-space()]">
<A>
<xsl:apply-templates select="following-sibling::node()[1][not(self::B)]" mode="sibling"/>
</A>
<xsl:apply-templates select="following-sibling::B[1]" mode="sibling"/>
</xsl:if>
</xsl:template>
</xsl:stylesheet>
An XSLT-1.0 solution - which is quite ugly - is the following. The output is as desired, but only for this simple MCVE. A general solution would be far more complicated as #michael.hor257k mentioned in the comments. Without more data it is unlikely to create a better solution in XSLT-1.0. Solutions for XSLT-2.0 and above may simplify this.
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:template match="/root">
<xsl:copy>
<xsl:for-each select="A">
<xsl:if test="normalize-space(text()[1])">
<A>
<xsl:copy-of select="text()[1]" />
</A>
</xsl:if>
<xsl:if test="preceding::*">
<xsl:copy-of select="B[1]" />
</xsl:if>
<A>
<xsl:copy-of select="C[1] | C[1]/following-sibling::text()[1] | D[1]" />
</A>
<xsl:if test="not(preceding::*)">
<xsl:copy-of select="B[1]" />
</xsl:if>
<A>
<xsl:copy-of select="C[2] | C[2]/following-sibling::text()[1]" />
<xsl:if test="D[2]">
<xsl:copy-of select="D[2]" />
</xsl:if>
</A>
<xsl:copy-of select="B[2]" />
<xsl:if test="normalize-space(text()[last()])">
<A>
<xsl:copy-of select="text()[last()]" />
</A>
</xsl:if>
</xsl:for-each>
</xsl:copy>
</xsl:template>
</xsl:stylesheet>
Concerning the situation of
<A><C>No</C></A>
<A><D>May be</D></A>
It is handled appropriately in the above code. So its output is
<A>
<C>No</C>
<D>May be</D>
</A>
Easy in XSLT 2 or 3 with group-adjacent=". instance of element(B)" or group-adjacent="boolean(self::B)", here is an XSLT 3 example (XSLT 3 is supported by Saxon 9.8 or 9.9 on Java and .NET (https://sourceforge.net/projects/saxon/files/Saxon-HE/) and by Altova since 2017 releases):
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
exclude-result-prefixes="#all"
version="3.0">
<xsl:mode on-no-match="shallow-copy"/>
<xsl:output indent="yes"/>
<xsl:strip-space elements="*"/>
<xsl:template match="A">
<xsl:for-each-group select="node()" group-adjacent=". instance of element(B)">
<xsl:choose>
<xsl:when test="current-grouping-key()">
<xsl:apply-templates select="current-group()"/>
</xsl:when>
<xsl:otherwise>
<xsl:copy select="..">
<xsl:apply-templates select="current-group()"/>
</xsl:copy>
</xsl:otherwise>
</xsl:choose>
</xsl:for-each-group>
</xsl:template>
</xsl:stylesheet>
https://xsltfiddle.liberty-development.net/gWmuiKv
In XSLT 2 you need to spell out the <xsl:mode on-no-match="shallow-copy"/> as the identity transformation template and use xsl:element instead xsl:copy:
<xsl:transform xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="2.0">
<xsl:template match="#*|node()">
<xsl:copy>
<xsl:apply-templates select="#*|node()"/>
</xsl:copy>
</xsl:template>
<xsl:output indent="yes"/>
<xsl:strip-space elements="*"/>
<xsl:template match="A">
<xsl:for-each-group select="node()" group-adjacent=". instance of element(B)">
<xsl:choose>
<xsl:when test="current-grouping-key()">
<xsl:apply-templates select="current-group()"/>
</xsl:when>
<xsl:otherwise>
<xsl:element name="{name(..)}" namespace="{namespace-uri(..)}">
<xsl:apply-templates select="current-group()"/>
</xsl:element>
</xsl:otherwise>
</xsl:choose>
</xsl:for-each-group>
</xsl:template>
</xsl:transform>
http://xsltransform.hikmatu.com/pPqsHT2

XSLT – creating a network from all children elements

With XSLT 2.0, I am trying to create a list of relations between all children of given elements, in a document such as:
<doc>
<part1>
<name>John</name>
<name>Paul</name>
<name>George</name>
<name>Ringo</name>
<place>Liverpool</place>
</part1>
<part2>
<name>Romeo</name>
<name>Romeo</name>
<name>Juliet</name>
<fam>Montague</fam>
<fam>Capulet</fam>
</part2>
</doc>
The result I would like to obtain, ideally by conflating and weighing the identical relations, would be (in whatever order) something like:
<doc>
<part1>
<rel><name>John</name><name>Paul</name></rel>
<rel><name>John</name><name>George</name></rel>
<rel><name>John</name><name>Ringo</name></rel>
<rel><name>Paul</name><name>George</name></rel>
<rel><name>Paul</name><name>Ringo</name></rel>
<rel><name>George</name><name>Ringo</name></rel>
<rel><name>John</name><place>Liverpool</place></rel>
<rel><name>Paul</name><place>Liverpool</place></rel>
<rel><name>George</name><place>Liverpool</place></rel>
<rel><name>Ringo</name><place>Liverpool</place></rel>
</part1>
<part2>
<rel weight="2"><name>Romeo</name><name>Juliet</name></rel>
<rel weight="2"><name>Romeo</name><fam>Montague</fam></rel>
<rel weight="2"><name>Romeo</name><fam>Capulet</fam></rel>
<rel><name>Juliet</name><fam>Montague</fam></rel>
<rel><name>Juliet</name><fam>Capulet</fam></rel>
<rel><fam>Montague</fam><fam>Capulet</fam></rel>
</part2>
</doc>
—but I'm not sure how to proceed. Many thanks in advance for your help.
You still haven't explained the logic that needs to be applied here, so this is based largely on a guess:
XSLT 2.0
<xsl:stylesheet version="2.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="xml" version="1.0" encoding="UTF-8" indent="yes"/>
<xsl:strip-space elements="*"/>
<!-- identity transform -->
<xsl:template match="/">
<xsl:copy>
<xsl:apply-templates select="#*|node()"/>
</xsl:copy>
</xsl:template>
<xsl:template match="doc/*">
<!-- first pass-->
<xsl:variable name="unique-items">
<xsl:for-each-group select="*" group-by="concat(name(), '|', .)">
<item name="{name()}" count="{count(current-group())}" value="{.}"/>
</xsl:for-each-group>
</xsl:variable>
<!-- output -->
<xsl:copy>
<xsl:for-each select="$unique-items/item">
<xsl:variable name="left" select="."/>
<xsl:for-each select="following-sibling::item">
<xsl:variable name="weight" select="$left/#count * #count" />
<rel>
<xsl:if test="$weight gt 1">
<xsl:attribute name="weight" select="$weight"/>
</xsl:if>
<xsl:apply-templates select="$left | ." />
</rel>
</xsl:for-each>
</xsl:for-each>
</xsl:copy>
</xsl:template>
<xsl:template match="item">
<xsl:element name="{#name}">
<xsl:value-of select="#value"/>
</xsl:element>
</xsl:template>
</xsl:stylesheet>
The idea here is to remove duplicates in the first pass, then enumerate all combinations in the second (final) pass. The weight is computed by multiplying the number of occurrences of each member of a combination pair and shown only when it exceeds 1.
At least the combinatoric part of your problem could be solved with the following XSLT script. It does not solve the elimination of duplicates, but that could possibly be done in a second transformation.
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<!-- standard copy template -->
<xsl:template match="node()|#*">
<xsl:copy>
<xsl:apply-templates select="node()|#*" />
</xsl:copy>
</xsl:template>
<xsl:template match="doc/*">
<xsl:copy>
<xsl:variable name="l" select="./*"/>
<xsl:for-each select="$l">
<xsl:variable name="a" select="."/>
<xsl:variable name="posa" select="position()"/>
<xsl:variable name="namea" select="name()"/>
<xsl:for-each select="$l">
<xsl:if test="position() > $posa and (. != $a or name() != $namea)">
<rel>
<xsl:copy-of select="$a"/>
<xsl:copy-of select="."/>
</rel>
</xsl:if>
</xsl:for-each>
</xsl:for-each>
</xsl:copy>
</xsl:template>
</xsl:stylesheet>
When applied to the first part of your example, this produces:
<part1>
<rel><name>John</name><name>Paul</name></rel>
<rel><name>John</name><name>George</name></rel>
<rel><name>John</name><name>Ringo</name></rel>
<rel><name>John</name><place>Liverpool</place></rel>
<rel><name>Paul</name><name>George</name></rel>
<rel><name>Paul</name><name>Ringo</name></rel>
<rel><name>Paul</name><place>Liverpool</place></rel>
<rel><name>George</name><name>Ringo</name></rel>
<rel><name>George</name><place>Liverpool</place></rel>
<rel><name>Ringo</name><place>Liverpool</place></rel>
</part1>
Which seems about correct. If have no idea if the duplicate elimination (or weighting, as you call it) could be done in the same transformation.

xslt generate children based on split and parent node name

is it possible to do the following in xsl. I'm tring to split the contents of an element and create sub-elements based on the split. To make things trickier there are the occasional exception (ie node-4 doesn't get split). I'm wondering if there is a way i can do this without explicit splits hardcoded for each element. Again, not sure if this is possible. thanks for the help!
original XML:
<document>
<node>
<node-1>hello world1</node-1>
<node-2>hello^world2</node-2>
<node-3>hello^world3</node-3>
<node-4>hello^world4</node-4>
</node>
</document>
transformed XML
<document>
<node>
<node-1>hello world1</node-1>
<node-2>
<node2-1>hello</node2-1>
<node2-2>world2</node2-2>
</node-2>
<node-3>
<node3-1>hello</node3-1>
<node3-2>world3</node3-2>
</node-3>
<node-4>hello^world4</node-4>
</node>
</document>
To make things trickier there are the
occasional exception (ie node-4
doesn't get split). I'm wondering if
there is a way i can do this without
explicit splits hardcoded for each
element.
Pattern matching text nodes to tokenize, this more semantic stylesheet:
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:template match="node()|#*">
<xsl:copy>
<xsl:apply-templates select="node()|#*"/>
</xsl:copy>
</xsl:template>
<xsl:template match="text()[contains(.,'^')]" name="tokenize">
<xsl:param name="pString" select="concat(.,'^')"/>
<xsl:param name="pCount" select="1"/>
<xsl:if test="$pString">
<xsl:element name="{translate(name(..),'-','')}-{$pCount}">
<xsl:value-of select="substring-before($pString,'^')"/>
</xsl:element>
<xsl:call-template name="tokenize">
<xsl:with-param name="pString"
select="substring-after($pString,'^')"/>
<xsl:with-param name="pCount" select="$pCount + 1"/>
</xsl:call-template>
</xsl:if>
</xsl:template>
<xsl:template match="node-4/text()">
<xsl:value-of select="."/>
</xsl:template>
</xsl:stylesheet>
Output:
<document>
<node>
<node-1>hello world1</node-1>
<node-2>
<node2-1>hello</node2-1>
<node2-2>world2</node2-2>
</node-2>
<node-3>
<node3-1>hello</node3-1>
<node3-2>world3</node3-2>
</node-3>
<node-4>hello^world4</node-4>
</node>
</document>
Note: A classic tokenizer (In fact, this use a normalized string allowing empty items in sequence). Pattern matching and overwriting rules (preserving node-4 text node).
Here's an XSL 1.0 solution. I presume that the inconsistency in node-4 in your sample output was just a typo. Otherwise you'll have to define why node3 was split and node4 wasn't.
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:xs="http://www.w3.org/2001/XMLSchema" version="1.0">
<xsl:output method="xml" indent="yes"/>
<xsl:template match="/">
<document>
<node>
<xsl:apply-templates select="document/node/*"/>
</node>
</document>
</xsl:template>
<xsl:template match="*">
<xsl:variable name="tag" select="name()"/>
<xsl:choose>
<xsl:when test="contains(text(),'^')">
<xsl:element name="{$tag}">
<xsl:element name="{concat($tag,'-1')}">
<xsl:value-of select="substring-before(text(),'^')"/>
</xsl:element>
<xsl:element name="{concat($tag,'-2')}">
<xsl:value-of select="substring-after(text(),'^')"/>
</xsl:element>
</xsl:element>
</xsl:when>
<xsl:otherwise>
<xsl:copy-of select="."/>
</xsl:otherwise>
</xsl:choose>
</xsl:template>
</xsl:stylesheet>
This works as long as all the nodes you want split are at the same level, under /document/node. If the real document structure is different you will have to tweak the solution to match.
Can you use XSLT 2.0? If so, it sounds like <xsl:analyze-string> is right up your alley. You can split based on a regexp.
If you need further details, ask...
solution i used:
<xsl:output omit-xml-declaration="yes" method="xml" indent="yes"/>
<xsl:preserve-space elements="*"/>
<xsl:template match="node()|#*" name="identity">
<xsl:copy>
<xsl:apply-templates select="node()[1]|#*"/>
</xsl:copy>
<xsl:apply-templates select="following-sibling::node()[1]"/>
</xsl:template>
<xsl:template match="node()" mode="copy">
<xsl:call-template name="identity"/>
</xsl:template>
<xsl:template match="node-2 | node-3" name="subFieldCarrotSplitter">
<xsl:variable name="tag" select="name()"/>
<xsl:element name="{$tag}">
<xsl:for-each select="str:split(text(),'^')">
<xsl:element name="{concat($tag,'-',position())}">
<xsl:value-of select="text()"/>
</xsl:element>
</xsl:for-each>
</xsl:element>
<xsl:apply-templates select="following-sibling::node()[1]"/>
</xsl:template>