# A Message-Passing Interpretation of Adjoint Logic

## TL;DR

This paper introduces a novel session type system based on adjoint logic that models complex asynchronous communication behaviors like multicast, replication, and cancellation, ensuring safety and deadlock-freedom.

## Contribution

It extends standard binary session types with a logical foundation, enabling uniform handling of advanced communication patterns and providing formal guarantees.

## Key findings

- Achieves session fidelity and deadlock-freedom.
- Provides a logically justified garbage collection method.
- Models multicast, replication, and cancellation behaviors.

## Abstract

We present a system of session types based on adjoint logic which generalize standard binary session types. Our system allows us to uniformly capture several new behaviors in the space of asynchronous message-passing communication, including multicast, where a process sends a single message to multiple clients, replicable services, which have multiple clients and replicate themselves on-demand to handle requests from those clients, and cancellation, where a process discards a channel without communicating along it. We provide session fidelity and deadlock-freedom results for this system, from which we then derive a logically justified form of garbage collection.