XSLT 2.0 array/map

geek.shrek · November 2nd, 2007, 06:41 AM

Hi,

Is there any "array" like in XSLT 2.0?
I would like to increment every key that I found.

For example:

<line>ABC</line> ==> will create key="ABC" value=1
<line>DEF</line> ==> will create key="DEF" value=1
<line>ABC</line> ==> will increment value key="ABC" by 1 (value= 2)

Any suggestion?

Cheers,

mhkay · November 2nd, 2007, 06:51 AM

XSLT 2.0 supports sequences, which are very like the arrays of other programming languages.

However, XSLT is a functional language, so values are immutable. I'm not sure you are thinking about your transformation task in the right way: could you explain the problem you are trying to solve, rather than the solution you are trying to design?

Michael Kay
http://www.saxonica.com/
Author, XSLT Programmer's Reference and XPath 2.0 Programmer's Reference

samjudson · November 2nd, 2007, 06:58 AM

You can't increment values, and XSLT doesn't have the concept of an array as such.

What about simply doing "count(line[string(.)='ABC'])".

You could use the distinct-values(line/text()) to get a list of unique values of line values.

Code:

<?xml version='1.0' encoding='utf-8' ?>
<lines>
    <line>ABC</line>
    <line>BC</line>
    <line>ABC</line>
    <line>NBC</line>
    <line>ABC</line>
    <line>BC</line>
</lines>



<xsl:template match="/">
<xsl:variable name="root" select="."/>
<xsl:for-each select="distinct-values(//line/text())">
    <xsl:sequence select="."/> = <xsl:sequence select="count($root//line[string(.)=current()])"/>
</xsl:for-each>
</xsl:template>

Produces: ABC = 3 BC = 2 NBC = 1

/- Sam Judson : Wrox Technical Editor -/

geek.shrek · November 2nd, 2007, 07:17 AM

Thanks for the reply :)

data example:
<data>
   <line>ABC 2007-11-01T12:00:01</line>
   <line>DEF 2007-11-01T12:00:01</line>
   <line>ABC 2007-11-01T13:60:02</line>
   <line>ABC 2007-11-01T17:60:02</line>
</data>

I have to read <line> one by one. Everytime I found for example "ABC", then I need to display how many I have read that "ABC"

so in this case when I read
* 1st <line> will produce something like
   <name counter="1">ABC</name>
* 2nd <line> will produce <name counter="1">DEF</name>
* 3rd <line> will produce <name counter="2">ABC</name>
* 4th <line> will produce <name counter="3">ABC</name>

I hope this explain my intention.

If XSLT can't produce this, is it possible if I parsing a parameter from XSLT to my java application? therefore I can send a parameter like "ABC" and get the java to do the counter and send me back the result.

Thanks,

mhkay · November 2nd, 2007, 09:03 AM

You don't have to read the lines one by one, you can process them all at once. That's what declarative programming is about.

Sounds like you want

<xsl:template match="line">
  <name counter="{1+count(preceding-sibling::line[.=current()]}">
    <xsl:value-of select="."/>
  </name>
</xsl:template>

Michael Kay
http://www.saxonica.com/
Author, XSLT Programmer's Reference and XPath 2.0 Programmer's Reference

samjudson · November 2nd, 2007, 10:20 AM

I think <xsl:number> might be able to do what you are after:

<xsl:template match="line">
    <name>
        <xsl:attribute name="counter">
            <xsl:number count="//line[text()=current()]"/>
        </xsl:attribute>
        <xsl:sequence select="."/>
    </name>
</xsl:template>

/- Sam Judson : Wrox Technical Editor -/