Subtyping and Matching for Mobile Objects

Abstract

Abstract. In [BCC00], we presented a general framework for extending calculi of mobile agents with object-oriented features, and we studied a typed instance of that model based on Cardelli and Gordon's Mobile Ambients. Here, we refine our earlier work and define a new calculus which is based on Remote Procedure Call as the underlying protocol for method invocation, and on a different typing technique for method bodies. The new type system is equipped with a subtyping and a matching relation: the combination of matching with subtyping provides new insight into the relationship between ambient opening in the new calculus and method overriding in object-oriented calculi.