ACM SIGPLAN Notices - POPL '14
Author's Final Manuscript
Open, type-level functions are a recent innovation in Haskell that move Haskell towards the expressiveness of dependent types, while retaining the look and feel of a practical programming language. This paper shows how to increase expressiveness still further, by adding closed type functions whose equations may overlap, and may have non-linear patterns over an open type universe. Although practically useful and simple to implement, these features go be- yond conventional dependent type theory in some respects, and have a subtle metatheory.
© ACM, 2014. This is the author's version of the work. It is posted here by permission of ACM for your personal use. Not for redistribution. The definitive version was published in ACM SIGPLAN Notices - POPL '14, Volume 49, Issue 1 (January 2014) http://doi.acm.org/10.1145/2578855.2535856
Richard A. Eisenberg, Dimitrios Vytiniotis, Simon Peyton Jones, Stephanie Weirich, "Closed type families with overlapping equations," ACM SIGPLAN Notices - POPL '14 49.1 (January 2014): 671-683.