Doaitse Swierstra (Utrecht University)
Atze Dijkstra (Utrecht University)
The Haskell type system is a quite elaborate, and implementing of all its features at the same time is no easy task. We will show how, by using a Haskell based attribute grammar approach, the problem can be handled in a fairly large number number of steps, each of which can be relatively easily understood. Besides the standard type inference, we will explain how to handle explicit type annotations and subsumption rules.