Question

I have a strangely formatted XML document which features a few tags that repeat; but I need to process this data using a tool that doesn’t support repeated tags.

Thus I need a way to concatenate the data within the repeated tags.

My initial document appears as follows:

<root>
    <irrelevantTag1>irrelevantData1</irrelevantTag1>
    <irrelevantTag2>irrelevantData2</irrelevantTag2>
    <irrelevantTag3>
        <irrelevantTag4>irrelevantData4</irrelevantTag4>
        <keyword>one</keyword>
        <keyword>two</keyword>
    </irrelevantTag3>
    <irrelevantTag5>irrelevantData5</irrelevantTag5>
</root>

I need a stylesheet to concatenate the values with the two “keyword” tags and produce a single keyword tag as in the following output:

<root>
    <irrelevantTag1>irrelevantData1</irrelevantTag1>
    <irrelevantTag2>irrelevantData2</irrelevantTag2>
    <irrelevantTag3>
        <irrelevantTag4>irrelevantData4</irrelevantTag4>
        <keyword>one,two</keyword>
    </irrelevantTag3>
    <irrelevantTag5>irrelevantData5</irrelevantTag5>
</root>

Answer 1

These two templates should do the trick:

<xsl:template match="keyword[1]">
   <keyword>
      <xsl:for-each select="../keyword">
         <xsl:if test=". != ../keyword[1]">,</xsl:if>
         <xsl:value-of select="."/>
      </xsl:for-each>
   </keyword>
</xsl:template>
<xsl:template match="keyword"/>

Use an apply-templates on a match for the parent element, or simply plug them into an identity transform.