{-# LANGUAGE MagicHash #-}
{-# LANGUAGE PolyKinds #-}
{-# LANGUAGE DataKinds #-}
{-# LANGUAGE RoleAnnotations #-}

unit number-unknown where
  signature NumberUnknown where
    import GHC.Types
    import GHC.Exts
    data Rep (l :: Levity) :: RuntimeRep
    data Number (l :: Levity) :: TYPE (Rep l)
    plus :: Number l -> Number l -> Number l
    multiply :: Number l -> Number l -> Number l
  module NumberStuff where
    import NumberUnknown
    funcA :: Number l -> Number l -> Number l
    funcA x y = plus x (multiply x y)
    -- should get a representation polymorphism error: 'Rep l' is not fixed.