A Compositional Trace Semantics for Orc

  • Dimitrios Vardoulakis
  • Mitchell Wand
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5052)


Orc [9] is a language for task orchestration. It has a small set of primitives, but sufficient to express many useful programs succinctly. We identify an ambiguity in the trace semantics of Kitchin et al. [9]. We give possible interpretations of the ambiguous definition and show that the semantics is not adequate regardless of the interpretation. We remedy this situation by providing new operational and denotational semantics with a better treatment of variable binding, and proving an adequacy theorem to relate them. Also, we investigate strong bisimulation in Orc and show that bisimulation implies trace equivalence but not vice versa.


Operational Semantic Internal Event Denotational Semantic Dynamic Binding Site Call 
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-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • Dimitrios Vardoulakis
    • 1
  • Mitchell Wand
    • 1
  1. 1.Northeastern University 

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