Engineering Theories of Software Intensive Systems

Volume 195 of the series NATO Science Series pp 331-350

A Tree Semantics of an Orchestration Language

  • Tony HoareAffiliated withMicrosoft Research Labs
  • , Galen MenzelAffiliated withUniversity of Texas
  • , Jayadev MisraAffiliated withUniversity of Texas

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This paper presents a formal semantics of a language, called Orc, which is described in a companion paper[3] in this volume. There are many styles of presentation of programming language semantics. The more operational styles give more concrete guidance to the implementer on how a program should be executed. The more abstract styles are more helpful in proving the correctness of particular programs. The style adopted in this paper is neutral between implementer and programmer. Its main achievement is to permit simple proofs of familiar algebraic identities that hold between programs with different syntactic forms.