On formalization of object model by unifying intensional and extensional representations

摘要

In this paper we present the consequences of unifying the representation of the schema and the instance levels of an object programming language to the formal representation of object model. The uniform representation of schema and instance levels of object languages is achieved, as in the frame-based knowledge representation languages [9], by representing them using a uniform set of modeling constructs. We show that, using such an approach, the structural part of the object language model can be described in a clear manner providing the simple means for the description of the main constructs of the structural model and the relationships among them. Further, we study the consequences of releasing the boundary between the schema and the instance levels of an object programming language by allowing the definition of objects which include data from both levels. We show that few changes are needed in order to augment the previously presented formal definition of the structural part of object language to represent the extended object model.