#8634: Relax functional dependency coherence check ("liberal coverage condition") -------------------------------------+------------------------------------- Reporter: danilo2 | Owner: Type: feature | Status: new request | Milestone: 7.10.1 Priority: high | Version: 7.7 Component: Compiler | Keywords: Resolution: | Operating System: Unknown/Multiple Differential Revisions: Phab:D69 | Type of failure: None/Unknown Architecture: | Test Case: Unknown/Multiple | Blocking: Difficulty: Unknown | Blocked By: | Related Tickets: #1241, | #2247, #8356, #9103, #9227 | -------------------------------------+------------------------------------- Comment (by goldfire): I'm not sure I understand comment:42, danilo2. The error you have toward the beginning of the comment is what I see when I leave out the fun-dep on `PolyMonad`. It doesn't seem related to my commented-out instance. Or, does un-commenting out the instance really produce that error? That's something strange. And, the `MatchMonad` idea just seems to kick the can down the road a bit: how could we have my desired instance for `MatchMonad` without `DysfunctionalDependencies`? Yes, `f` will type-check, but it won't be able to be called. Or am I deeply confused? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/8634#comment:43 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler