fn:exactly-one

Checks whether $arg contains exactly one item; fails if it is empty or contains multiple items.

exactly-one($arg as item()*) ➔ item()

Arguments

 

$arg

item()*

The sequence to be tested

Result

item()

Namespace

http://www.w3.org/2005/xpath-functions

Links to W3C specifications

XPath 3.1 Functions and Operators

Saxon availability

Available in XPath 2.0, XSLT 2.0, XQuery 1.0, and later versions. Available in all Saxon editions.