#13981: Family instance consistency checks happens too early when hs-boot defined type occurs on LHS -------------------------------------+------------------------------------- Reporter: ezyang | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler (Type | Version: 8.2.1-rc2 checker) | Resolution: | Keywords: hs-boot 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):
right now, we decide to defer a type family consistency check if the family was recursively defined.
I don't like the sound of that. Strange deferring under special circumstances. Can we figure out a more uniform approach? I've lost context here. In your example, modules `B` and `C` seem to have no overlap problem, but `A` does. Can you set out the problem you are trying to solve, ab-initio? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13981#comment:1 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler