EPSILON: A System Description Language

This paper presents the Epsilon language and defines its formal syntax and semantics. Epsilon is a language for the description of systems, which contain concurrent components, some of these being edp-equipment or by other means representing highly structured information handling. The actions consist of continuous changes described by equations, of communication between the components and of normal algorithmic actions.Epsilon may be used for the description of computer systems together with their environments, e.g. production equipment and human operators. Parts of such a description may serve as the system specification from which computer programs are developed. Epsilon is not itself an implementable language.This paper defines the semantics of Epsilon by means of a model based on high-level Petri nets, i.e. a model founded on the notion of concurrency. The model also uses denotational semantics and equation systems