#9111: base should export Typeable instances of its promoted data constructors -------------------------------------+------------------------------------ Reporter: goldfire | Owner: Type: feature request | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.8.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Unknown/Multiple Type of failure: None/Unknown | Difficulty: Unknown Test Case: | Blocked By: Blocking: | Related Tickets: -------------------------------------+------------------------------------ Comment (by hvr): Replying to [comment:14 simonpj]:
{{{ Failed to load interface for ‘Data.Typeable.Internal’ }}}
btw, that message is just asking to add an `import Data.Typeable.Internal` in the module triggering that error (which often isn't possible due to import-cycles)
Can you explain how to reproduce this error. Just add `AutoDeriveTypeable` to `base.cabal`? Or what?
Adding `default-extension: AutoDeriveTypeable` to `base.cabal` is one way. But a more interesting case to try out is to enable `AutoDeriveTypeable` just inside a single module such as `GHC/Flaot.lhs` which doesn't `import Data.Typeable` -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9111#comment:15 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler