Asynchronous Functional Sessions: Cyclic and Concurrent

TL;DR

This paper introduces Concurrent GV, a session-typed calculus supporting advanced concurrency features like cyclic topologies, with formal semantics, translation to APCP, and deadlock-freedom guarantees.

Contribution

It extends prior calculi with enhanced concurrency support and provides a formal translation and deadlock analysis technique.

Findings

CGV supports cyclic and concurrent network topologies.

A correct translation from CGV to APCP is established.

Deadlock-free CGV programs are achievable using APCP's priority system.

Abstract

We present Concurrent GV (CGV), a functional calculus with message-passing concurrency governed by session types. With respect to prior calculi, CGV has increased support for concurrent evaluation and for cyclic network topologies. The design of CGV draws on APCP, a session-typed asynchronous pi-calculus developed in prior work. Technical contributions are (i) the syntax, semantics, and type system of CGV; (ii) a correct translation of CGV into APCP; (iii) a technique for establishing deadlock-free CGV programs, by resorting to APCP's priority-based type system.