Epic—A Library for Generating Compilers

Compilers for functional languages, whether strict or non-strict, typed or untyped, need to handle many of the same problems, for example thunks, lambda lifting, optimisation, garbage collection, and system interaction. Although implementation techniques are by now well understood, it remains difficult for a new functional language to exploit these techniques without either implementing a compiler from scratch, or attempting to fit the new language around another existing compiler. Epic is a compiled functional language which exposes functional compilation techniques to a language implementor, with a Haskell API. In this paper we describe Epic and outline how it may be used to implement a high level language compiler, illustrating our approach by implementing compilers for the λ-calculus and a dynamically typed graphics language.