Abstract

Abstract There are a number of research efforts directed at adding advancedtyping features such as, guarded recursive data types, type classes, dependent types etc. to Haskell-style language. By and large, theseextensions have been studied independently. Here, we present a unifying formal framework to study these features. Thus, we canexpress some novel variants such as extended algebraic data types and various forms of lexically scoped type annotations. We pro-vide numerous examples to show the usefulness of these features. Furthermore, we have implemented these extensions as part of theChameleon system (an experimental version of Haskell). Hence, we can greatly extend the expressiveness of languages such asHaskell.

Citations

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