#14873: The well-kinded type invariant (in TcType) -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: goldfire Type: bug | Status: merge Priority: highest | Milestone: 8.6.1 Component: Compiler (Type | Version: 8.5 checker) | Resolution: | Keywords: TypeInType Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple crash or panic | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by goldfire): I've wondered about this, too. If we had `TcType` separate from `Type`, then we this would be very easy to find. I suppose we could smoke it out: put an `ASSERT` in the `typeKind` case for `TyVarTy` that the tyvar isn't a `TcTyVar`. Do the same with `eqType`. Then we'd catch (almost) all the cases. I wonder what the performance implications would be. (+) We don't have to zonk unnecessarily just to maintain the invariant. (-) When we do zonk, we don't memorialize this in the type -- only in the kind. (-) Is monadic code slower than pure code? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14873#comment:13 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler