Abstract

OCaml is a modern functional language which is used by a range of professional organisations, from Facebook and Citrix to Bloomberg. It provides the ability to write fast, functional code in a modular way, through its use of classes and modules. OCaml uses a static type system which utilises type inference, to ensure safety. Type inference systems allow the programmer to write few type annotations and let the compiler infer the types; this improves readability and code comprehension, which are important features in any language; while guaranteeing no run-time type errors.

This talk will give a brief introduction to the OCaml language, with a focus on comparing OCaml to the similar functional language SML . The talk will then discuss the type system which OCaml uses, including its use of objects, including OCaml’s version of structural polymorphism, and polymorphic variants. After which I will present a simple implementation of the Hindley-Milner type inference algorithm applied to a small OCaml-like language. HM is a simple, but fast, algorithm which has been proven correct.