A typed null value, used to assign a null value to an attribute, a variable or return null from a method.

someobject.someattribute := <Type>.nullValue

Example

Given a Car class We can create a variable vCar

vCar:Car

And add name

vCar:= Car.Create;
vCar.Name:='Ferari x'

Now We can unset the Name attribute using nullValue like this

vCar.Name:=String.nullValue

Do not use <Type>.nullValue to compare something to null, like this

vCurrent_UppdragTyp = Uppdragstyp.nullValue    -- WRONG

For comparing to null, use the operators .isNull or .notNull