Re: [xsl] XPath selecting chain of following siblings of the same name

["Mukul Gandhi" <gandhi.mukul@xxxxxxxxx>]

I wonder, why this XSLT 1.0 solution doesn't work:

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform";
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[not(preceding-sibling::*[1][self::a])]">
  <a-block>
    <xsl:copy-of select="." />
    <xsl:apply-templates select="following-sibling::*[1][self::a]" />
  </a-block>
</xsl:template>

</xsl:stylesheet>

I have tried to code the sibling-recursion technique for "positional
grouping" suggested by Michael Kay long time ago.

I'll be grateful if anyone let me know what's wrong with the above code.

On 3/9/07, Kolacm Toma <kolaci@xxxxxxx> wrote:
> Hi!
>
> I have following input XML:
>
>  <root>
>    <a id="1"/>
>    <a id="2"/>
>    <b/>
>    <d/>
>    <g/>
>    <a id="3"/>
>    <a id="4"/>
>    <a id="5"/>
>    <x/>
>    <a id="6"/>
>    <a id="7"/>
>  </root>
>
> and I'm trying to create XSLT 1.0 script, which would nest "uninterrupted"
sibling groups of 'a' elements into 'a-block' elements, so the output would
look like:
>  <root>
>    <a-block>
>      <a id="1"/>
>      <a id="2"/>
>    </a-block>
>    <b/>
>    <d/>
>    <g/>
>    <a-block>
>      <a id="3"/>
>      <a id="4"/>
>      <a id="5"/>
>    </a-block>
>    <x/>
>    <a-block>
>      <a id="6"/>
>      <a id="7"/>
>    </a-block>
>  </root>
>
> How should look XPath selecting next 'a' elements of the same group in
template matching first group element?
> I was able to create this (see second xsl:copy-of) (derived from
http://www.biglist.com/lists/xsl-list/archives/200208/msg01182.html idea):
>  <xsl:template match="a">
>    <xsl:if test="not(preceding-sibling::*[1][self::a])"> <!-- first node of
each group -->
>      <xsl:element name="a-block">
>        <xsl:copy-of select="."/>
>        <xsl:copy-of select="following-sibling::a
>          [preceding-sibling::*[1][self::a]]
[generate-id(preceding-sibling::a[not(preceding-sibling::*[1][self::a])][1]) =
generate-id(current())]"/>
>          <!-- first condition selects only 2nd+ nodes of each group -->
>          <!-- second condition checks if the 1st node of the group is the
current one -->
>      </xsl:element>
>    </xsl:if>
>  </xsl:template>
>
> and it works (as far as I have test it up to now), but it's ugly, there must
be something simpler..?
> Thanks in advance!
>
> Best regards, Tomas Kolaci
> ____________________
>
> Full script (it does not handle white spaces correctly, but it does not
matter in this case):
> <?xml version="1.0" encoding="UTF-8"?>
> <xsl:stylesheet
>  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"; version="1.0">
>
>  <xsl:output method="xml" indent="no"/>
>
>  <xsl:template match="root">
>    <xsl:copy>
>      <xsl:apply-templates/>
>    </xsl:copy>
>  </xsl:template>
>
>  <xsl:template match="a">
>    <xsl:if test="not(preceding-sibling::*[1][self::a])"> <!-- first node of
each group -->
>      <xsl:element name="a-block">
>        <xsl:copy-of select="."/>
>        <xsl:copy-of select="following-sibling::a
>          [preceding-sibling::*[1][self::a]]
[generate-id(preceding-sibling::a[not(preceding-sibling::*[1][self::a])][1]) =
generate-id(current())]"/>
>          <!-- first condition selects only 2nd+ nodes of each group -->
>          <!-- second condition checks if the 1st node of the group is the
current one -->
>      </xsl:element>
>    </xsl:if>
>  </xsl:template>
>
>  <xsl:template match="*">
>    <xsl:copy-of select="."/>
>  </xsl:template>
>
> </xsl:stylesheet>


--
Regards,
Mukul Gandhi