#13732: Incorrectly suggests ‘TypeOperators’ -------------------------------------+------------------------------------- Reporter: Iceland_jack | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.1 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- Loading the code {{{#!hs {-# Language RankNTypes, GADTs, MagicHash, PolyKinds, TypeInType, ConstraintKinds #-} import Data.Kind import GHC.Exts import qualified Prelude class Semi (a :: TYPE rep) where data Free :: forall rep. (TYPE rep -> Constraint) -> TYPE rep -> Type where Free :: (forall q. ctx q => (p -> q) -> q) -> Free ctx p }}} gives an incorrect suggestion {{{ GHCi, version 8.2.0.20170507: http://www.haskell.org/ghc/ :? for help [1 of 1] Compiling Main ( tXMX.hs, interpreted ) Ok, modules loaded: Main. *Main> :kind Free Semi Free Semi :: * -> * *Main> :kind Free Semi Int# <interactive>:1:1: error: Not in scope: type constructor or class ‘#’ <interactive>:1:1: error: Illegal operator ‘#’ in type ‘Free Semi Int #’ Use TypeOperators to allow operators in types <interactive>:1:1: error: Operator applied to too few arguments: Free Semi Int # *Main> }}} This should recommend enabling `MagicHash` instead. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13732 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler