fn:dateTime

Combines the given date and time. The result has a timezone if either of the inputs has a timezone; if they both have a timezone, then the two timezones must be the same.

dateTime($arg1 as xs:date?, $arg2 as xs:time?) ➔ xs:dateTime?

Namespace

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

Links to W3C specifications

XPath 3.1 Functions and Operators

Notes on the Saxon implementation

The result will be an instance of xs:dateTimeStamp, and retains nanosecond precision (or more typically, the precision of the system clock).