A PredefinedField object stores the non-propagating data of a predefined field as well as a number of instances of the corresponding PredefinedFieldState object. The PredefinedFieldState object stores the propagating data of the predefined field in a single step. A specific type of PredefinedField object and a specific type of PredefinedFieldState object are designed for each type of predefined field. Instances of the PredefinedFieldState object are created and deleted internally by its corresponding PredefinedField object.