An Analysis of -calculus Bisimulations
نویسندگان
چکیده
The-calculus is a relatively simple framework in which the semantics of the dynamic creation and transmission of channels can be studied. We consider in particular the issue of deening and verifying the equivalence of-terms in the context of bisimulation based semantics. We distinguish three main contributions: (1) A characterization ofèarly' bisimulation in terms of a notion of`contextual' bisimulation. (2) The deenition of a-calculus with explicit substitutions and the description of an abstract machine based on this notation which incrementally computes the synchronization tree of a-process. (3) The introduction of a reenement of thèlate' bisimulation which we calìuniform'. Roughly the latter corresponds to the idea of treating the formal parameter of an input preex as a `logical' variable. It is argued that this might lead to more eecient veriication tools. Finally, as an example of the expressive power of the-calculus, we show how this calculus can be used in the representation of a natural implementation of an environment machine for the call-by-name-calculus.
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