Inheritance in Higher Order Logic: Modeling and Reasoning

This paper describes a way of modeling inheritance (in object-oriented programming languages) in higher order logic. This particular approach is used in the LOOP project for reasoning about JAVA classes, with the proof tools PVS and ISABELLE. It relies on nested interface types to capture the superclasses, fields, methods, and constructors of classes, together with suitable casting functions incorporating the difference between hiding of fields and overriding of methods. This leads to the proper handling of late binding, as illustrated in several verification examples.