XSLT Reference

type-available()

XSLT 2.0 node function

Returns true if the schema type named by the argument is available in the static context.

Syntax

type-available(type-name)

Description

type-available() tests whether a named XML Schema type is known to the processor in the current static context. The argument is a string containing the lexical QName of the type, resolved against the in-scope namespace bindings. The function returns true if the type exists and can be used for casting, instance-of tests, or schema validation; otherwise it returns false.

This function is used in conjunction with xsl:if or xsl:when to write portable stylesheets that adapt their behavior based on which schema types have been imported. Built-in schema types from the xs: namespace are always available. User-defined types from imported schemas are available only when schema-awareness is active.

Parameters

Parameter	Type	Required	Description
`type-name`	xs:string	Yes	The lexical QName of the schema type to test, resolved in the current namespace context.

Return value

xs:boolean — true if the named type is available, false otherwise.

Examples

Conditional behavior based on schema type availability

Input XML:

<?xml version="1.0" encoding="UTF-8"?>
<data>
  <value>42</value>
</data>

Stylesheet:

<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="2.0"
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
  xmlns:xs="http://www.w3.org/2001/XMLSchema">
  <xsl:output method="xml" indent="yes"/>

  <xsl:template match="/data">
    <result>
      <xsl:choose>
        <xsl:when test="type-available('xs:integer')">
          <typed><xsl:value-of select="xs:integer(value) * 2"/></typed>
        </xsl:when>
        <xsl:otherwise>
          <untyped><xsl:value-of select="value * 2"/></untyped>
        </xsl:otherwise>
      </xsl:choose>
    </result>
  </xsl:template>
</xsl:stylesheet>

Output:

<result>
  <typed>84</typed>
</result>

Checking for a user-defined type

Stylesheet:

<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="2.0"
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
  xmlns:app="http://example.com/schema">
  <xsl:output method="text"/>

  <xsl:template match="/">
    <xsl:choose>
      <xsl:when test="type-available('app:ProductCode')">
        <xsl:text>User-defined type is available</xsl:text>
      </xsl:when>
      <xsl:otherwise>
        <xsl:text>Running without schema import</xsl:text>
      </xsl:otherwise>
    </xsl:choose>
  </xsl:template>
</xsl:stylesheet>

Output (without schema import):

Running without schema import

Notes

All types in the xs: namespace are available in any XSLT 2.0 or later processor that supports the XML Schema built-in types, regardless of whether any schema has been imported.
User-defined types must be imported with xsl:import-schema before they are recognized by type-available().
type-available() tests availability at runtime, but type names must still be resolved at compile time using in-scope namespaces.
The analogous functions function-available() and element-available() test for XSLT extension functions and elements respectively.