#9858: Typeable instances should be kind-aware -------------------------------------+------------------------------------- Reporter: dreixel | Owner: dreixel Type: bug | Status: new Priority: highest | Milestone: 7.10.1 Component: Compiler | Version: 7.9 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: None/Unknown | Unknown/Multiple Blocked By: | Test Case: Related Tickets: | Blocking: | Differential Revisions: -------------------------------------+------------------------------------- Comment (by goldfire): I vote for Simon's option 1 -- just make runtime type identification a feature of GHC Haskell, exposed through the `Typeable` interface. This will take a small amount of work to engineer, but I think the end state will be simpler than what we have now, and likely more efficient. I will point out one drawback: I believe users will be confused about the need for `Typeable` constraints. After all, if ''every'' type is `Typeable`, then why include the constraint? We cognoscenti know that the `Typeable` constraint is just implicitly passing the runtime witness, but we'll have to be careful to explain this to those who think that class constraints are all about logical statements, not implicit type-determined parameters. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9858#comment:21 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler