SAXONICA

Saxon Documentation

Full Contents

About Saxon

Changes in this Release

Notices

Using XSLT 2.0

Using XQuery

Handling Source Documents

XML Schema Processing

XPath API for Java

Saxon on .NET

Extensibility

Saxon Extensions

Sample Saxon Applications

The Saxon SQL Extension

XSLT Elements

XPath 2.0 Expression Syntax

Function Library

Standards Conformance

fn:zero-or-one

fn:zero-or-one($srcval as item*) as item?

Function signature

$srcval	item() *
Result	item() ?

Tests whether $srcval contains zero or one items; fails if it contains multiple items.

XPath 2.0 Specification