Re: [xsl] How to do this tricky elimination on XML using XSLT 2.0?

[Geert Bormans <geert@xxxxxxxxxxxxxxxxxxx>]

This could get you started

<?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";
    xmlns:pfn="private"
    exclude-result-prefixes="xs pfn"
    version="2.0">
    <xsl:template match="node()">
        <xsl:copy>
            <xsl:copy-of select="@*"/>
            <xsl:apply-templates select="node()"/>
        </xsl:copy>
    </xsl:template>

    <xsl:template match="*[@id][@method][pfn:is-duplicate(.)]">
        <removed/>
    </xsl:template>

    <xsl:function name="pfn:is-duplicate" as="xs:boolean">
        <xsl:param name="this-node" as="element()"/>
        <xsl:value-of select="count($this-node/(preceding-sibling::* 
| ../preceding-sibling::*[@id = $this-node/parent::*/@id]/*)[name() = 
$this-node/name()][@id = $this-node/@id][deep-equal(*, 
$this-node/*)][@method = $this-node/@method]) mod 2 = 1"/>
    </xsl:function>
</xsl:stylesheet>




At 11:14 19/06/2012, Jo Na wrote:
> Hi,
> I have this input xml:
>     <map>
>         <region>
>             <gridA id="1">
>                 <blockA id="01" method="build">
>                     <building1 id="x" method="build">
>                         <otherchild>a</otherchild>
>                     </building1>
>                     <building1 id="x" method="build"> <!-- this one
> will be removed -->
>                         <otherchild>a</otherchild>
>                     </building1>
>                 </blockA>
>
>                 <blockA id="01">
>                     <building1 id="x" method="modify">
>                         <otherchild>a</otherchild>
>                     </building1>
>                     <building1 id="x" method="build"> <!-- this one
> will be kept (prev node have same id but diff method so it's not
> considered as successive -->
>                         <otherchild>a</otherchild>
>                     </building1>
>                 </blockA>
>
>                 <blockA id="02">
>                     <building3 id="y" method="modify">
>                         <otherchild>b</otherchild>
>                     </building3>
>                     <building2 id="x" method="demolish"/>
>                 </blockA>
>
>                 <blockA id="01">
>                     <building1 id="y" method="build"> <!-- this one
> will be kept (diff id) -->
>                         <otherchild>a</otherchild>
>                     </building1>
>                     <building1 id="x" method="build"> <!-- this one
> will be removed -->
>                         <otherchild>a</otherchild>
>                     </building1>
>                 </blockA>
>
>                 <blockA id="02">
>                     <building3 id="y" method="modify"> <!-- this one
> will be removed -->
>                         <otherchild>b</otherchild>
>                     </building3>
>                     <building2 id="x" method="demolish"/> <!-- this
> one will be removed -->
>                 </blockA>
>             </gridA>
>
>             <gridA id="2">
>                 <blockA id="01" method="build">
>                     <building1 id="x" method="build">
>                         <otherchild>a</otherchild>
>                     </building1>
>                     <building1 id="x" method="build"> <!-- this one
> will be removed -->
>                         <otherchild>a</otherchild>
>                     </building1>
>                     <building1 id="x" method="build"> <!-- this one
> will be kept (diff children) -->
>                         <otherchild>b</otherchild>
>                     </building1>
>                 </blockA>
>                 <blockA id="01">
>                     <building1 id="x" method="build"> <!-- this one
> will be removed -->
>                         <otherchild>b</otherchild>
>                     </building1>
>                 </blockA>
>             </gridA>
>             <gridB id="1">
>                 ...and so on..
>             </gridB>
>         </region>
>     </map>
>
> Expected Output:
>
>     <map>
>         <region>
>             <gridA id="1">
>                 <blockA id="01" method="build">
>                     <building1 id="x" method="build">
>                         <otherchild>a</otherchild>
>                     </building1>
>                 </blockA>
>
>                 <blockA id="01">
>                     <building1 id="x" method="modify">
>                         <otherchild>a</otherchild>
>                     </building1>
>                     <building1 id="x" method="build"> <!-- this one
> will be kept (prev node have same id but diff method so it's not
> considered as successive -->
>                         <otherchild>a</otherchild>
>                     </building1>
>                 </blockA>
>
>                 <blockA id="02">
>                     <building3 id="y" method="modify">
>                         <otherchild>b</otherchild>
>                     </building3>
>                     <building2 id="x" method="demolish"/>
>                 </blockA>
>
>                 <blockA id="01">
>                     <building1 id="y" method="build"> <!-- this one
> will be kept (diff id) -->
>                         <otherchild>a</otherchild>
>                     </building1>
>                 </blockA>
>
>                 <blockA id="02"/>
>             </gridA>
>
>             <gridA id="2">
>                 <blockA id="01" method="build">
>                     <building1 id="x" method="build">
>                         <otherchild>a</otherchild>
>                     </building1>
>
>                     <building1 id="x" method="build"> <!-- this one
> will be kept (diff children) -->
>                         <otherchild>b</otherchild>
>                     </building1>
>                 </blockA>
>                 <blockA id="01"/>
>             </gridA>
>             <gridB id="1">
>                 ...and so on..
>             </gridB>
>         </region>
>     </map>
> The XSLT so far:
>
>     <xsl:stylesheet version="2.0"
> xmlns:xsl="http://www.w3.org/1999/XSL/Transform";>
>         <xsl:output indent="yes"/> <xsl:strip-space elements="*"/>
>
>         <xsl:template match="node()|@*">
>             <xsl:copy>
>                 <xsl:apply-templates select="node()|@*"/>
>             </xsl:copy>
>         </xsl:template>
>
>         <xsl:template match="region/*/*/*
>              [deep-equal(.,preceding::*[name()=current()/name()]
>                            [@id = current()/@id]
>                            [../../@id = current()/../../@id][1])]" />
>     </xsl:stylesheet>
>
> the problem with the XSLT right now is that it cannot differentiate
> duplicates that happens in siblings (i.e blockA with the same id).
>
> I need to remove a node that are considered as *repetitive*.
>
> **Two node that have the same `name` and `id` will be considered
> *repetitive* if it appears one after another and it has the same
> `method` and `children`.**
>
> **for example:**
>
>     <elem id="1" method="a" />
>     <elem id="1" method="a" /> <!-- this is repetitive for id=1-->
>     <elem id="1" method="b" />
>     <elem id="1" method="a" /> <!-- this is the new boundary for 
> removal id=1-->
>     <elem id="2" method="a" />
>     <elem id="1" method="a" /> <!-- this is repetitive for id=1 -->
>     <elem id="2" method="a" /> <!-- this is repetitive for id=2 -->
>
> **will be simplified into:**
>
>     <elem id="1" method="a" />
>     <elem id="1" method="b" />
>     <elem id="1" method="a" /> <!-- this is the new boundary for 
> removal id=1-->
>     <elem id="2" method="a" />
>
>  **- Everytime a successive node with the `same id` has `different method`,
>    the `boundary` for the next removal for that `id` is reset.**
>
>  - we need to take into account duplicates that are under one parent
> or siblings (two or more parents nodes that has the same element name
> and id) i.e (in example: `blockX`)
>  - if the two nodes being compared did not share the same `gridX`
> level, then they should not be considered as duplicates to be removed
>
> Please let me know how to achieve such transformation using XSLT 2.0.
> Thanks very much for the help.