Conference Proceedings
Sound and decidable type inference for functional dependencies
GJ Duck, S Peyton-Jones, PJ Stuckey, M Sulzmann
Lecture Notes in Computer Science Including Subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics | SPRINGER-VERLAG BERLIN | Published : 2004
Abstract
Functional dependencies are a popular and useful extension to Haskell style type classes. In this paper, we give a reformulation of functional dependencies in terms of Constraint Handling Rules (CHRs). In previous work, CHRs have been employed for describing user-programmable type extensions in the context of Haskell style type classes. Here, we make use of CHRs to provide for the first time a concise result that under some sufficient conditions, functional dependencies allow for sound and decidable type inference. The sufficient conditions imposed on functional dependencies can be very limiting. We show how to safely relax these conditions. © Springer-Verlag 2004.