Re: [xsl] how with xPath 1

[Leo Studer <leo.studer@xxxxxxxxxxx>]

Hi Ken

thank you for your lines.

The question came up in class. I teach xPath and asked the students how to
retrieve the first CD of each artist.
Here the xPath 1 which does the job:
	//cd[not(artist = preceding-sibling::cd/artist)]

A student asked how to retrieve the newest CD of each artist.
I told the student, that I know how to do that with xPath 2.0 and gave this
solution
	for $i in distinct-values(//artist) return (//cd[artist eq $i and year=
max(//cd[artist eq $i ]/year)])

The problem is, that in xPath 1 we have neither "for" nor "distinct-values()".
So I wonder, is it possible to retrieve the newest cd of each artist with
xPath 1 only.

Your proposition with XSLT 1 is nice, thank you.

Greetings
Leo




T:\ftemp>type leo.xml
<?xml version="1.0" encoding="ISO-8859-1"?>
<cdcatalog>
  <cd>
     <title>Empire Burlesque</title>
     <artist>Bob Dylan</artist>
     <country>USA</country>
     <company>Columbia</company>
     <price>10.90</price>
     <year>1985</year>
  </cd>
  <cd>
     <title>Hide your heart</title>
     <artist>Bonnie Tyler</artist>
     <country>UK</country>
     <company>CBS Records</company>
     <price>9.90</price>
     <year>1988</year>
  </cd>
  <cd>
     <title>The Times They Are a-Changin'</title>
     <artist>Bob Dylan</artist>
     <country>USA</country>
     <company>Columbia</company>
     <price>10.90</price>
     <year>1964</year>
  </cd>
  <cd>
     <title>Faster Than The Speed of Light</title>
     <artist>Bonnie Tyler</artist>
     <country>UK</country>
     <company>Columbia</company>
     <price>9.90</price>
     <year>1983</year>
  </cd>
  <cd>
     <title>Time Out of Mind</title>
     <artist>Bob Dylan</artist>
     <country>USA</country>
     <company>Columbia</company>
     <price>10.90</price>
     <year>1997</year>
  </cd>
</cdcatalog>
T:\ftemp>xslt leo.xml leo.xsl
<?xml version="1.0" encoding="utf-8"?>
For Bonnie Tyler found Hide your heart 1988
For Bob Dylan found Time Out of Mind 1997
T:\ftemp>type leo.xsl
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform";
 version="1.0">

<xsl:key name="cds-by-artist" match="cd" use="artist"/>

<xsl:template match="cdcatalog">
 <!--select those in the latest year for each artist-->
 <xsl:for-each select="cd[not(year &lt; key('cds-by-artist',artist)/year)]">
   <!--report findings-->
   <xsl:text>
</xsl:text>
   <xsl:value-of select="concat('For ',artist,' found ',title,' ',year)"/>
 </xsl:for-each>
</xsl:template>

</xsl:stylesheet>
T:\ftemp>xquery leo.xquery
<?xml version="1.0" encoding="UTF-8"?>
<cd>
     <title>Time Out of Mind</title>
     <artist>Bob Dylan</artist>
     <country>USA</country>
     <company>Columbia</company>
     <price>10.90</price>
     <year>1997</year>
  </cd>
<cd>
     <title>Hide your heart</title>
     <artist>Bonnie Tyler</artist>
     <country>UK</country>
     <company>CBS Records</company>
     <price>9.90</price>
     <year>1988</year>
  </cd>
T:\ftemp>type leo.xquery




T:\ftemp>