XSLT

Name

function-available() Function — Determines if a given function is available to the XSLT processor. This function allows you to design stylesheets that react gracefully if a particular function is not available to process an XML document.

Synopsis

boolean function-available(
               string
               )

Inputs

The name function’s name. The name is usually qualified with a namespace; if the namespace of the function name is non-null, the function is an extension function. Otherwise, the function is one of the functions defined in the XSLT or XPath specifications.

Output

The boolean value true if the function is available, false otherwise.

Defined in

XSLT section 15, Fallback.

Example

We’ll use the following XML document to test the function-available() function:

<?xml version="1.0"?>
<list>
  <title>A few of my favorite albums</title>
  <listitem>A Love Supreme</listitem>
  <listitem>Beat Crazy</listitem>
  <listitem>Here Come the Warm Jets</listitem>
  <listitem>Kind of Blue</listitem>
  <listitem>London Calling</listitem>
  <listitem>Remain in Light</listitem>
  <listitem>The Joshua Tree</listitem>
  <listitem>The Indestructible Beat of Soweto</listitem>
</list>

Here’s our stylesheet:

<?xml version="1.0"?> <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:jpeg="class:JPEGWriter" extension-element-prefixes="jpeg"> <xsl:output method="text"/> <xsl:variable name="newline"> <xsl:text> </xsl:text> </xsl:variable> <xsl:template match="/"> <xsl:value-of select="$newline"/> <xsl:for-each select="list/listitem"> ...