Re: Does XSL support an eval?

["G. Ken Holman" <gkholman@xxxxxxxxxxxxxxxxxxxx>]

At 00/05/02 02:23 +1000, JamesW@xxxxxxxxxxxxxxx wrote:
> Is there a way in XSL to take an XPath query described in a parameter or 
> variable, and reference this parameter in the select attribute of say, 
> xsl:for-each to iterate through the node set described by the query.
>
> ie.
>
> <xsl:variable name="myPath" select="'/my/XPath/@query'"/>
> <xsl:for-each select="{$myPath}">
>         ...
> </xsl:for-each>
>
> We were under the impression that using the curly braces might achieve 
> this, but haven't had any luck so far.

You are *so* close that I hope you don't get hurt kicking yourself.

Using standard XSLT 1.0 (no extensions) you can assign a node set to a 
variable using an XPath expression ... unfortunately, you quoted your 
expression which is assigning a string value to the variable, not a node 
set.  When you assign a node set and you remove the brace brackets you 
have, it works just fine (see example below).

I hope this helps.

................ Ken


T:\ftemp>type test.xml
<?xml version="1.0"?>
<my>
 <XPath query="first">
 </XPath>
 <XPath query="third">
 </XPath>
 <XPath query="second">
 </XPath>
</my>

T:\ftemp>type test.xsl
<?xml version="1.0"?>

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform";
                version="1.0">

<xsl:output method="text"/>

<xsl:template match="/">                         <!--root rule-->
  <xsl:variable name="myPath" select="/my/XPath/@query"/>
  <xsl:for-each select="$myPath">
    <xsl:text>Value: </xsl:text>
    <xsl:value-of select="."/>
    <xsl:text>&#xd;&#xa;</xsl:text>
  </xsl:for-each>
</xsl:template>

</xsl:stylesheet>

T:\ftemp>xt test.xml test.xsl
Value: first
Value: third
Value: second

T:\ftemp>

--
G. Ken Holman                    mailto:gkholman@xxxxxxxxxxxxxxxxxxxx
Crane Softwrights Ltd.             http://www.CraneSoftwrights.com/s/
Box 266, Kars, Ontario CANADA K0A-2E0   +1(613)489-0999   (Fax:-0995)
Web site: XSL/XML/DSSSL/SGML services, training, libraries, products.
Practical Transformation Using XSLT and XPath      ISBN 1-894049-04-7
Next instructor-led training:               2000-05-11/12,2000-05-15,
-                                    2000-06-12,2000-06-13,2001-01-27


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