Type Classes for Lightweight Substructural Types

Edward Gan
Jesse A. Tov
(Northeastern University)
Greg Morrisett
(Harvard University)

Linear and substructural types are powerful tools, but adding them to standard functional programming languages often means introducing extra annotations and typing machinery. We propose a lightweight substructural type system design that recasts the structural rules of weakening and contraction as type classes; we demonstrate this design in a prototype language, Clamp.

Clamp supports polymorphic substructural types as well as an expressive system of mutable references. At the same time, it adds little additional overhead to a standard Damas-Hindley-Milner type system enriched with type classes. We have established type safety for the core model and implemented a type checker with type inference in Haskell.

In Sandra Alves and Iliano Cervesato: Proceedings Third International Workshop on Linearity (LINEARITY 2014), Vienna, Austria, 13th July, 2014, Electronic Proceedings in Theoretical Computer Science 176, pp. 34–48.
Published: 16th February 2015.

ArXived at: http://dx.doi.org/10.4204/EPTCS.176.4 bibtex PDF
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