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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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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