public FEELFnResult < TemporalAmount > invoke ( @ ParameterName ( "from" ) TemporalAmount val ) { if ( val == null ) { return FEELFnResult . ofError ( new InvalidParametersEvent ( Severity . ERROR , "from" , "cannot be null" ) ) ; } return FEELFnResult . ofResult ( val ) ; }
This is the identity function implementation