Mechanized analysis of behavioral conformance in the Eiffel Base Libraries

Abstract

We report on an analysis of the inheritance relationships in the Eiffel Base Libraries, a library of container data structures. If inheritance is behaviorally conforming, then polymorphism can be used safely, and the inheritance hierarchy can be considered part of the interface of the library to its clients. We describe a theory of object-oriented specification in higher-order logic that we used to specify part of the Eiffel Base Libraries. With the theorem prover Isabelle/HOL, we mechanically prove conformance relationships between those specifications. This work allows us to draw conclusions about the design of the Eiffel Base Libraries, and about the feasibility of using an interactive theorem prover to apply a strictly formal theory to the specification of a commercial product. © Springer-Verlag Berlin Heidelberg 2001.