Re: [xsl] XPath equivalence question

[Hermann Stamm-Wilbrandt <STAMMW@xxxxxxxxxx>]

Have you tried out what you propose as equivalent below?

No XSLT processor is doing what you say, xsltproc, saxon, DataPower, ...

$ saxon Graydon.1.xsl Graydon.xml ; echo
<?xml version="1.0" encoding="UTF-8"?><B/>
$
$ saxon Graydon.2.xsl Graydon.xml ; echo
<?xml version="1.0" encoding="UTF-8"?>
$
$ cat Graydon.xml
<A><a><b><c><B/></c></b></a></A>
$
$ cat Graydon.1.xsl
<xsl:stylesheet version="1.0"
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform";
>
  <xsl:output method="xml"/>

  <xsl:template match="/">
    <xsl:copy-of select="/A//B"/>
  </xsl:template>

</xsl:stylesheet>
$
$ cat Graydon.2.xsl
<xsl:stylesheet version="1.0"
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform";
>
  <xsl:output method="xml"/>

  <xsl:template match="/">
    <xsl:copy-of select="B[/A]"/>
  </xsl:template>

</xsl:stylesheet>
$


Mit besten Gruessen / Best wishes,

Hermann Stamm-Wilbrandt
Level 3 support for XML Compiler team, Fixpack team lead
WebSphere DataPower SOA Appliances
https://www.ibm.com/developerworks/mydeveloperworks/blogs/HermannSW/
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  From:       Graydon <graydon@xxxxxxxxx>                                                                                               
                                                                                                                                        
  To:         xsl-list@xxxxxxxxxxxxxxxxxxxxxx,                                                                                          
                                                                                                                                        
  Date:       12/01/2011 12:50 AM                                                                                                       
                                                                                                                                        
  Subject:    [xsl] XPath equivalence question                                                                                          
                                                                                                                                        
  Sent by:    <graydon@xxxxxxxxx>                                                                                                       
                                                                                                                                        





Does

<xsl:template match="/A//B">

match exactly the same thing as

<xsl:template match="B[/A]">?

My presumption is that the second form is preferable on efficiency
grounds -- on simple table lookup versus whatever tree-structure the
descendant axis search produces -- but I don't actually know.

-- Graydon