A typing system for a calculus of objects

  • Vasco T. Vasconcelos
  • Mario Tokoro
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 742)


The present paper introduces an implicitly typed object calculus intended to capture intrinsic aspects of concurrent objects communicating via asynchronous message passing, together with a typing system assigning typings to terms in the calculus. Types meant to describe the kind of messages an object may receive are assigned to the free names in a program, resulting in a scenario where a program is assigned multiple name-type pairs, constituting a typing for the process. Programs that comply to the typing discipline are shown not to suffer from runtime errors. Furthermore the calculus possesses a notion of principal typings, from which all typings that make a program well-typed can be extracted. We present an efficient algorithm to extract the principal typing of a process.


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  1. [1]
    Carl Hewitt. Viewing control structures as patterns of passing messages. Artificial Inteligence, 8(3):323–364, 1977.CrossRefGoogle Scholar
  2. [2]
    Kohei Honda. Types for Dyadic Interaction. In Proceedings of CONCUR'93, Springer-Verlag, LNCS, August 1993.Google Scholar
  3. [3]
    Kohei Honda and Mario Tokoro. An Object Calculus for Asynchronous Communication. In 1991 European Conference on Object-Oriented Computing, pages 141–162, Springer-Verlag, 1991. LNCS 512.Google Scholar
  4. [4]
    Robin Milner. The Polyadic π-Calculus: a Tutorial. ECS-LFCS 91-180, University of Edinburgh, October 1991.Google Scholar
  5. [5]
    Atsushi Ohori. A compilation method for ML-style polymorphic record calculi. In 19th ACM Symposium on Principles of Programming Languages, pages 154–165, 1992.Google Scholar
  6. [6]
    Vasco T. Vasconcelos. A predicative polymorphic type system for the polyadic π-calculus. May 1993. Keio University.Google Scholar
  7. [7]
    Vasco T. Vasconcelos and Kohei Honda. Principal typing-schemes in a polyadic π-calculus. In Proceedings of CONCUR'93, Springer-Verlag, LNCS, August 1993.Google Scholar
  8. [8]
    Mitchell Wand. A simple algorithm and proof for type inference. Fundamenta Informaticae, X:115–122, 1987. North-Holland.Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1993

Authors and Affiliations

  • Vasco T. Vasconcelos
    • 1
  • Mario Tokoro
    • 1
    • 2
  1. 1.Department of Computer ScienceKeio UniversityYokohamaJapan
  2. 2.Sony Computer Science LaboratoryJapan

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