An operational semantics for stac, a language for modelling long-running business transactions

Abstract. This paper presents the StAC language and its operational semantics. StAC (Structured Activity Compensation) is a business process modelling language and a distinctive feature of the language is its support for compensation. A compensation is an action taken to recover from error or cope with a change of plan, especially when rollback of a process is not possible. StAC is similar to a process algebraic language such as Hoare’s CSP or Milner’s CCS but has additional operators dealing with compensation and with exception handling. We have developed an operational semantics for the language which is presented in this paper.