#12466: Typechecker regression: Inaccessible code in a type expected by the context -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: Type: bug | Status: new Priority: highest | Milestone: 8.2.1 Component: Compiler (Type | Version: 8.1 checker) | Resolution: | Keywords: 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 goldfire): I think comment:4 is unrelated. (But let's not lose the fact that there is a terrible pretty-printing bug there, without parentheses around the equality argument to `Dict`.) The commit in comment:7 is all about instances, and comment:4 is unrelated to instances. Yes, I think the original code should produce a warning. To suppress the warning, the user should include an implementation of `foo`, so that the generic-default implementation (which has the wrong type) is not used. But if inaccessible code is an error, then the original code should produce an error, just as it is now. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12466#comment:8 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler