#11471: Kind polymorphism and unboxed types: bad things are happening -------------------------------------+------------------------------------- Reporter: bgamari | Owner: goldfire Type: bug | Status: new Priority: normal | Milestone: Component: Compiler (Type | Version: 7.10.3 checker) | Keywords: TypeInType, Resolution: | LevityPolymorphism Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Changes (by simonpj): * owner: => goldfire Comment: Richard and I developed a plan this afternoon. '''Principle''': the kind of a type tells you its runtime representation (both width and pointer-hood). Currently we have {{{ data Levity = Lifted | Unlifted }}} With this new principle we would have {{{ data Levity = L -- Lifted, boxed, represented by a pointer | UB -- Unlifted, boxed, represented by a pointer | UV -- Unboxed, zero width | UW32 -- Unboxed, represented by a 32 bit word | UW64 -- Unboxed, represented by a 64 bit word | UF32 -- Unboxed, represented by a 32 bit float | UF64 -- Unboxed, represented by a 64 bit float ...etc... }}} Pretty much one case for each constructor in `PrimRep`. And that's it really. Now `typePrimRep` just takes the kind, and converts it to a `PrimRep`. This is a nice generalisation, and (we think) solves the problem. We need a Levity wiki page!! -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11471#comment:7 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler