XSLT Reference

xsl:package

XSLT 3.0 element

The root element of an XSLT 3.0 package, a named and versioned reusable unit of stylesheet components.

Syntax

<xsl:package name="com.example.pkg" package-version="1.0" version="3.0">

Description

xsl:package is the root element of a standalone XSLT 3.0 package — a named, versioned unit of XSLT logic that can be shared and reused across multiple stylesheets. Packages are the primary modularity mechanism in XSLT 3.0, superseding the xsl:import and xsl:include mechanisms for library authoring.

A package has a URI name (the name attribute) and a version string (the package-version attribute). The version attribute specifies the XSLT version in use (always 3.0 for packages). Components within the package are private by default; use xsl:expose to make them accessible to consuming stylesheets.

Packages can use other packages via xsl:use-package. A consuming stylesheet uses xsl:use-package to import the package and optionally overrides or re-exposes components.

Parameters

Parameter	Type	Required	Description
`name`	xs:anyURI	Yes	A URI that uniquely identifies the package.
`package-version`	string	Yes	A version string for this package (e.g. `"1.0"` or `"2.3.1"`).
`version`	string	Yes	XSLT version — must be `"3.0"` for packages.
`id`	xs:ID	No	An optional XML ID for the package element.
`input-type-annotations`	keyword	No	Controls type annotation stripping: `preserve`, `strip`, or `unspecified`.

Return value

xsl:package is a structural container; it produces no direct output.

Examples

A simple utility package

Package file (math-utils.xsl):

<?xml version="1.0" encoding="UTF-8"?>
<xsl:package version="3.0"
  name="http://example.com/math-utils"
  package-version="1.0"
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
  xmlns:xs="http://www.w3.org/2001/XMLSchema"
  xmlns:math="http://example.com/math-utils">

  <xsl:expose component="function" match="math:*" visibility="public"/>

  <xsl:function name="math:square" as="xs:double">
    <xsl:param name="n" as="xs:double"/>
    <xsl:sequence select="$n * $n"/>
  </xsl:function>

  <xsl:function name="math:cube" as="xs:double">
    <xsl:param name="n" as="xs:double"/>
    <xsl:sequence select="$n * $n * $n"/>
  </xsl:function>
</xsl:package>

Consuming the package

Stylesheet:

<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="3.0"
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
  xmlns:math="http://example.com/math-utils">
  <xsl:output method="xml" indent="yes"/>

  <xsl:use-package name="http://example.com/math-utils" package-version="1.*"/>

  <xsl:template match="/">
    <results>
      <square><xsl:value-of select="math:square(5)"/></square>
      <cube><xsl:value-of select="math:cube(3)"/></cube>
    </results>
  </xsl:template>
</xsl:stylesheet>

Output:

<results>
  <square>25</square>
  <cube>27</cube>
</results>

Notes

A package file uses xsl:package as its root element instead of xsl:stylesheet or xsl:transform. An xsl:package element may not have a named initial template that serves as the transformation entry point — it is a library, not a runnable transformation.
The package-version string follows no required format, but a dotted version scheme (e.g. 1.2.3) is conventional and supported by version pattern matching in xsl:use-package.
Packages can use other packages, enabling layered library architectures.
Processor-specific configuration is needed to tell the processor where to find packages referenced by name.