Modeling statecharts and activitycharts as signal equations
ACM Transactions on Software Engineering and Methodology
The languages for modelling reactive systems are of di erent styles, like the imperative, state-based ones and the declarative, data-ow ones. They are adapted to di erent application domains. This paper, through the example of the languages Statecharts and Signal, shows a way to give a model of an imperative speci cation (Statecharts) in a declarative, equational one (Signal). This model constitutes a formal model of the Statemate semantics of Statecharts, upon which formal analysis techniques
... an be applied. Being a transformation from an imperative to a declarative structure, it involves the de nition of generic models for the explicit management of state (in the case of control as well as of data). In order to obtain a structural construction of the model, a hierarchical and modular organization is proposed, including proper management and propagation of control along the hierarchy. The results presented here cover the essential features of Statecharts as well as of another language of Statemate: Activitycharts. As a translation, it makes multi-formalism speci cation possible, and provides support for the integrated operation of the languages. The motivation lies also in the perspective of gaining access to the various formal analysis and implementation tools of the synchronous technology, using the DC+ exchange format, as in the Sacres programming environment.