Re: [GHC] #13809: TH-reified type familly and data family instances have a paucity of kinds (was: TH-reified data family instances have a paucity of kinds)

9 Jun 2017

      #13809: TH-reified type familly and data family instances have a paucity of kinds
-------------------------------------+-------------------------------------
        Reporter:  RyanGlScott       |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Template Haskell  |              Version:  8.0.1
      Resolution:                    |             Keywords:  TypeFamilies
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by RyanGlScott):

 This also affects type family instances:

 {{{#!hs
 {-# LANGUAGE TypeFamilies #-}
 module Foo where

 type family Foo a
 type instance Foo ((f :: *        -> *) (a ::       *))  = Int
 type instance Foo ((f :: (* -> *) -> *) (a :: (* -> *))) = Char
 }}}

 {{{#!hs
 FamilyI
   (OpenTypeFamilyD
      (TypeFamilyHead
         Foo.Foo
         [ KindedTV a_6989586621679013859 StarT ]
         (KindSig StarT)
         Nothing))
   [ TySynInstD
       Foo.Foo
       (TySynEqn
          [ AppT (VarT f_6989586621679013869) (VarT a_6989586621679013868)
 ]
          (ConT GHC.Types.Char))
   , TySynInstD
       Foo.Foo
       (TySynEqn
          [ AppT (VarT f_6989586621679013874) (VarT a_6989586621679013873)
 ]
          (ConT GHC.Types.Int))
   ]
 }}}

--
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13809#comment:1
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