An object-oriented model based on relations
Abstract This work recognizes the importance of relationships between objects in the design of object-oriented systems. Such relationships exist that represent constraints between objects to be maintained at run-time. Maintaining these constraints requires that objects react in a coordinated fashion to incoming messages. We propose an object-oriented model where relationships play a central role. Relationships are used to describe the structure of complex objects in terms of their component parts, and to express more general constraints. This model makes semantic relationships accessible to the user, as they should be. It also simplifies the design of complex systems.