Typed object-oriented functional programming with late binding

Abstract

Object-oriented programming languages are suitable for describing real-world objects, functional programming languages for algebraic values. In this paper we propose an object-oriented functional programming language, called TOFL, which combines many desired properties of the two paradigms. In particular, TOFL unifies object classes, inheritance, (method) redefinitions and late binding as in object-oriented languages, algebraic data types, higher-order functions, type classes and type inference (without type reconstruction in this paper) as in functional languages. We translate TOFL into a stratified and explicitly typed λ-calculus T with overloaded functions, where redefinitions and late binding become late binding of overloaded functions. The operational semantics of T gives a semantics and a simple prototyping implementation of TOFL.