A LOTOS Simulator in OBJ

  • Kazuhito Ohmaki
  • Koichi Takahashi
  • Kokichi Futatsugi
Part of the Advances in Formal Methods book series (ADFM, volume 2)


In this paper, we show how to write a LOTOS simulator using OBJ. Both syntax rules and their inference rules (axioms) of LOTOS can be formally specified by operator definition part and equation definition part in OBJ, respectively.

When writing the simulator using a term rewriting system, we need a lazy evaluation mechanism, because rewriting operations for recursive process definitions in LOTOS would not terminate without lazy evaluation. We use this lazy evaluation mechanism of OBJ to realize the simulator. Powerful features like theory, view, and parameterized modules of OBJ are fruitfully used to write the simulator.

Using OBJ as an implementation language, we can also use the power of the abstract data type features of OBJ. This leads to the enhancement of LOTOS in future, especially for abstract data type enhancement. The introduction of subsort is one of the most distinguished point of using OBJ. This point is discussed using simple examples.

We also show an example to prove properties of a LOTOS specification.


Behavior Expression Inference Rule Operational Semantic Label Transition System Process Algebra 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer Science+Business Media New York 2000

Authors and Affiliations

  • Kazuhito Ohmaki
    • 1
  • Koichi Takahashi
    • 1
  • Kokichi Futatsugi
    • 1
  1. 1.Electrotechnical Laboratory1-1-4 UmeZonoTsukubaIbaraki 305Japan

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