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Can't apply higher-ranked kind in type family

This code doesn't typecheck due to F2:

{-# LANGUAGE RankNTypes #-}
{-# LANGUAGE TypeFamilies #-}
{-# LANGUAGE TypeInType #-}
module Bug where

import Data.Kind

f :: (forall (a :: Type). a -> a) -> Bool
f g = g True

type F1 (g :: forall (a :: Type). a -> a) = g True

type family F2 (g :: forall (a :: Type). a -> a) :: Bool where
  F2 g = g True
$ /opt/ghc/8.2.1/bin/ghci Bug.hs
GHCi, version 8.2.0.20170623: http://www.haskell.org/ghc/  :? for help
Loaded GHCi configuration from /home/rgscott/.ghci
[1 of 1] Compiling Bug              ( Bug.hs, interpreted )

Bug.hs:14:6: error:
    • Expected kind ‘forall a. a -> a’, but ‘g’ has kind ‘Bool -> Bool’
    • In the first argument of ‘F2’, namely ‘g’
      In the type family declaration for ‘F2’
   |
14 |   F2 g = g True
   |      ^

This is surprising to me, since F2 seems like the type family counterpart to f and F1, both of which typecheck.

Trac metadata
Trac field Value
Version 8.0.1
Type Bug
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler (Type checker)
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture
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