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arXiv · 2404.16213

MAG$\pi$!: The Role of Replication in Typing Failure-Prone Communication

Matthew Alan Le Brun·Ornela Dardha
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Abstract

MAG$\pi$ is a Multiparty, Asynchronous and Generalised $\pi$-calculus that introduces timeouts into session types as a means of reasoning about failure-prone communication. Its type system guarantees that all possible message-loss is handled by timeout branches. In this work, we argue that the previous is unnecessarily strict. We present MAG$\pi$!, an extension serving as the first introduction of replication into Multiparty Session Types (MPST). Replication is a standard $\pi$-calculus construct used to model infinitely available servers. We lift this construct to type-level, and show that it simplifies specification of distributed client-server interactions. We prove properties relevant to generalised MPST: subject reduction, session fidelity and process property verification.

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Matthew Alan Le Brun, Ornela Dardha. 2024-04-24. MAG$\pi$!: The Role of Replication in Typing Failure-Prone Communication. https://arxiv.org/abs/2404.16213

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