Eriskay : a programming language based on game semantics

We report on an ongoing project to design a strongly typed, class-based objectoriented language based around ideas from game semantics. Part of our goal is to create a powerful modern programming language whose clean semantic basis renders it amenable to work in program verification; however, we argue that our semantically inspired approach also yields benefits of more immediate relevance to programmers, such as expressive new language constructs and novel type systems for enforcing security properties of the language. We describe a simple-minded game model with a rich mathematical structure, and explain how this model may be used to guide the design of our language. We then focus on three specific areas where our approach appears to offer something new: linear types and continuations; observational equivalence for class types; and static control of the use of higher-order store. In a substantial appendix, we present the formal definition of a fragment of our language which embodies many of the innovative features of the full language.