Context-Free Session Type Inference

Some interesting communication protocols can be precisely described only by context-free session types, an extension of conventional session types supporting a general form of sequential composition. The complex metatheory of context-free session types, however, hinders the definition of corresponding checking and inference algorithms. In this work, we study a new syntax-directed type system for context-free session types that is easy to embed into a host programming language. We also detail 2 OCaml embeddings that allow us to piggyback on OCaml’s type system to check and infer context-free session types.