An example proof of correctness for a collaboration-based design

Object-oriented designs often achieve flexible composition, efficiency, and extensibility by separating concerns into roles, implemented as objects which collaborate to solve a problem or compute a function. Unfortunately, rigorous theories and proof techniques for collaboration-based designs are not as mature as those for their functional counterparts. Moreover, experience shows that it can be difficult to “wrap your mind” around sophisticated collaborations to understand if and how they work. The key result of this paper is an example proof of corrrectness of a design abstraction, called an inference graph, that is used by the Amalia software-analyzer generator. An inference graph is a complex network of objects that collaborate to compute an analysis. The proof is novel because it is structured to conform to the collaborative nature of inference graphs.