#11411: GHC allows you to quantify variables over TYPE 'Unlifted (a.k.a, #) -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.1 (Type checker) | Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: GHC accepts Unknown/Multiple | invalid program Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- This should be disallowed, so [https://phabricator.haskell.org/D1757 sayeth goldfire]: {{{ $ inplace/bin/ghc-stage2 --interactive GHCi, version 8.1.20160109: http://www.haskell.org/ghc/ :? for help λ> :set -XKindSignatures λ> import GHC.Types λ> data Wat (a :: TYPE 'Unlifted) = Wat a λ> :i Wat data Wat (a :: #) = Wat a -- Defined at <interactive>:3:1 λ> :set -XMagicHash λ> :t Wat 1# Wat 1# :: Wat GHC.Prim.Int# λ> :t Wat 'a'# Wat 'a'# :: Wat GHC.Prim.Char# }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11411 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler