David Broman
Department of Computer and Information Science, LinkÄoping University, Sweden
Peter Fritzon
Department of Computer and Information Science, LinkÄoping University, Sweden
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Published in: Proceedings of the 1st International Workshop on Equation-Based Object-Oriented Languages and Tools
Linköping Electronic Conference Proceedings 24:10, p. 111–126
Published: 2007-07-18
ISBN: 978-91-7519-822-4
ISSN: 1650-3686 (print), 1650-3740 (online)
Modelica is an open standardized language used for modeling and simulation of complex physical systems. The language speci cation defines a formal concrete syntax; but the semantics is informally described using natural language. The latter makes the language hard to interpret; maintain and reason about; which affect both tool development and language evolution. Even if a completely formal semantics of the Modelica language can be seen as a natural goal; it is a well- known fact that defining understandable and concise formal semantics specifications for large and complex languages is a very hard problem. In this paper; we will discuss different aspects of formulating a Modelica specification; both in terms of what should be specified and how it can be done. Moreover; we will further argue that a "middle-way" strategy can make the specification both clearer and easier to reason about. A proposal is outlined; where the current informally specified semantics is complemented with several context-sensitive grammars; specifying intermediate representations of abstract syntax. We believe that this kind of evolutionary strategy is easier to gain acceptance for; and is more realistic in the short-term; than a revolutionary approach of using a fullyformal semantics definition of the language.
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