The Expressiveness of CSP With Priority

The author previously [16,15] defined CSP-like operational semantics whose main restrictions were the automatic promotion of most tau actions, no cloning of running processes, and no negative premises in operational semantic rules. He showed that every operator with such an operational semantics can be translated into CSP and therefore has a semantics in every model of CSP. In this paper we demonstrate that a similar result holds for CSP extended by the priority operator described in Chapter 20 of [15], with the restriction on negative premises removed.