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arXiv · 2101.06249

Manifestly Phased Communication via Shared Session Types

Chuta Sano·Stephanie Balzer·Frank Pfenning
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Abstract

Session types denote message protocols between concurrent processes, allowing a type-safe expression of inter-process communication. Although previous work demonstrate a well-defined notion of subtyping where processes have different perceptions of the protocol, these formulations were limited to linear session types where each channel of communication has a unique provider and client. In this paper, we extend subtyping to shared session types where channels can now have multiple clients instead of a single client. We demonstrate that this generalization can statically capture protocol requirements that span multiple phases of interactions of a client with a shared service provider, something not possible in prior proposals. Moreover, the phases are manifest in the type of the client.

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Chuta Sano, Stephanie Balzer, Frank Pfenning. 2021-01-15. Manifestly Phased Communication via Shared Session Types. https://arxiv.org/abs/2101.06249

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