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PSL: A Semantic Domain for Flow Models



Conrad Bock, Michael Gruninger


Flow models underlie popular programming languages and many graphical behavior specification tools. However, their semantics is typically ambiguous, causing miscommunication between modelers and unexpected implementation results. This article introduces a way to disambiguate common flow modeling constructs, by expressing their semantics as constraints on runtime sequences of behavior execution. It also shows that reduced ambiguity enables more powerful modeling abstractions, such as partial behavior specifications. The runtime representation considered in this paper uses the Process Specification Language (PSL), which is defined in first-order logic, making it amenable to automated reasoning. The activity diagrams of the Unified Modeling Language are used for example flow models.
Software and Systems Modeling Journal


activity model, control flow, data flow, flow model, flow semantics, process specification, PSL, UML


Bock, C. and Gruninger, M. (2005), PSL: A Semantic Domain for Flow Models, Software and Systems Modeling Journal, [online],, (Accessed June 14, 2024)


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Created April 30, 2005, Updated October 12, 2021