date:parse-date definition:
string date:parse-date(string, string)
XPath you’re requesting when compiled ends up by searching for following function
string date:parse-date(nodeSet, string)
and thus can’t be found.
The solution is to force the first argument of the function to string as well. This can be done with AS:NodeToString.
AS:LookupValue(
'8f623352-bfaf-4e7a-bf56-1e9be280ca96',
'OnWay_par_DumpId',
/ROOT/dumpId,
'OnWay_parFleetVehicleIdId',
/ROOT/loaderId,
'OnWay_parLoadTimeStart',
date:parse-date(AS:NodeToString(/ROOT/timeStart), 'yyyyMMddHHmmss'))
There are no plans to adjust this behaviour.