#9627: Type error with functional dependencies -------------------------------------+------------------------------------- Reporter: augustss | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler (Type | Version: 7.8.3 checker) | Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by simonpj):
Does that "inability" date to before the FDs via CHRs 2006 paper?
I think that [https://people.cs.kuleuven.be/~tom.schrijvers/portfolio/haskell2017a.html Elaboration on functional dependencies] (Karachalias and Schrijvers, 2017) does he job nicely. Indeed they use the above example in their motivation section. It describes how to translate fundeps into type families -- so the intermediate language is exactly System FC, as today. I never implemented this, but if someone did then fundeps would acquire the same expressive power as type families. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9627#comment:4 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler