#15351: QuantifiedConstraints ignore FunctionalDependencies -------------------------------------+------------------------------------- Reporter: aaronvargo | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler (Type | Version: 8.5 checker) | Keywords: Resolution: | QuantifiedConstraints Operating System: Unknown/Multiple | Architecture: Type of failure: GHC rejects | Unknown/Multiple valid program | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by simonpj): Yes, you are right. Generally, when solving a constraint, GHC checks it against all in-scope instances in case there's fundep match. The same should happen for in-scope quantified constraints. Would anyone like to fix this? It's intriguing -- I never expected people to explore the outer limits of quantified constraints so rapidly. I hope that means that they are proving useful (when not so close to the limits). Is that so? Experience reports or blog posts (like Ryan Scott's) would be fascinating. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15351#comment:6 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler