Model verification in λΣ: a type inference approach

In this paper we describe a number of model analysis and verification operations based on type inference in the Xa simulation language. Ag is a simulation language based on the typed X-calculus. Xa entities correspond to typed X-expressions, while Xa activities correspond to subtypes. Thus, entities can be generated by means of type-introduction rules, and operations can be defined on entities by means of type elimination and equality rules. Premises of the form e E r in an introduction rule used to create a new entity can be satisfied by substituting for e any entity of type r in a neighboring activity. It is then possible to perform a number of model analysis and verification operations using type inference algorithms available for the typed X-calculus.