A Stable Model Semantics for Behavioral

We present a model for deductive object oriented query languages with inheritance and overriding. In this model, we consider a DAG like dynamic isa hierarchy and we account for both value or attribute inheritance and method inheritance or code sharing. We show that these two types of inheritance can be treated uniformly within an elegant declarative setting. We then propose a novel semantics for the non-monotonic behavior resulting from the combination of overriding, dynamic self binding and the dynamic structure of the isa hierarchy. This semantics is reminiscent of the stable model semantics of logic programs with negation. We also isolate a syntactic condition that guarantees the existence of a unique stable model for a program. This condition, in its turn, is inspired by the local stratiication condition of perfect model semantics for programs with negation. Finally we deene a bottom-up procedure that computes the unique stable model of a stratiied program.