xsl:template

Defines a processing rule for source elements or other nodes of a particular type.

Category: declaration
Content: ( xsl:context-item? , xsl:param* , sequence-constructor )
Permitted parent elements: xsl:package ; xsl:stylesheet ; xsl:transform ; xsl:override

Attributes

match?

pattern

Pattern to identify the type of node to be processed. The most common form of pattern is simply an element name. However, more complex patterns may also be used: the syntax of patterns is given in more detail in XSLT Pattern Syntax. The following examples show some of the possibilities:

Pattern

Meaning

XXX

Matches any element whose name (tag) is XXX

*

Matches any element

XXX/YYY

Matches any YYY element whose parent is an XXX

XXX//YYY

Matches any YYY element that has an ancestor named XXX

/*/XXX

Matches any XXX element that is immediately below the root (document) element

*[@ID]

Matches any element with an ID attribute

XXX[1]

Matches any XXX element that is the first XXX child of its parent element. (Note that this kind of pattern can be very inefficient: it is better to match all XXX elements with a single template, and then use xsl:if to distinguish them)

SECTION[TITLE="Contents"]

Matches any SECTION element whose first TITLE child element has the value Contents

A/TITLE | B/TITLE | C/TITLE

Matches any TITLE element whose parent is of type A or B or C

text()

Matches any character data node

@*

Matches any attribute

/

Matches the document node

name?

eqname

If this is present, the template may be invoked directly using xsl:call-template. The match attribute then becomes optional.

priority?

decimal

If there are several xsl:template elements that all match the same node, the one that is chosen is determined by the optional priority attribute: the template with highest priority wins. The priority is written as a floating-point number; the default priority is 1. If two matching templates have the same priority, the one that appears last in the stylesheet is used.

mode?

tokens

If this is present, the template will only be matched when the same mode is used in the invoking xsl:apply-templates element. The value can be a list of mode names, indicating that the template matches more than one mode; this list can include the token #default to indicate that the template matches the default (unnamed) mode. Alternatively the mode attribute can be set to #all, to indicate that the template matches all modes. (This can be useful in conjunction with xsl:next-match; one can write a template rule that matches in all modes, and then call xsl:next-match to continue processing in the original mode.)

as?

sequence-type

Defines the required type of the result. The result of evaluating the sequence constructor is converted to this required type using the function conversion rules. The default is item()*.

visibility?

"public" | "private" | "final" | "abstract"

New in XSLT 3.0. Determines the potential visibility of the component corresponding to this template; the default is private.

saxon:as?

Allows additional type information to be supplied using Saxon extension syntax. For details see saxon:as.

Notes on the Saxon implementation

The extension attribute saxon:explain can be used on an xsl:template element. If the attribute has value yes, then at compile time Saxon outputs (to the standard error output) a representation of the optimized expression tree for that template.

Saxon-EE 9.8 introduces just-in-time compilation of template rules. With this enabled, the static analysis of a template rule happens only the first time that the rule fires. This dramatically reduces compilation costs for large stylesheets that define many rules for rarely-used elements (the DITA and DocBook stylesheets are typical examples). This has the consequence that static errors in unused rules may go unreported. The feature can therefore be disabled, for example by using -opt:-j on the command line.

Examples

A simple XSLT template for a particular element. This example causes all <ptitle> elements in the source document to be output as HTML <h2> elements.

<xsl:template match="ptitle"> <h2> <xsl:apply-templates/> </h2> </xsl:template>

Links to W3C specifications

XSLT 2.0 Specification

XSLT 3.0 Specification

See also

xsl:apply-templates

xsl:apply-imports

xsl:call-template