#12647: Can't capture improvement of functional dependencies -------------------------------------+------------------------------------- Reporter: Iceland_jack | Owner: Type: task | Status: new Priority: normal | Milestone: Component: None | Version: 8.0.1 Resolution: | Keywords: | FunctionalDependencies 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 goldfire): Instance improvement happens only when you have a "wanted" constraint -- that is, when you're typechecking a function call of `f` where `f` has a class constraint with a functional dependency. Does that help? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12647#comment:3 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler