Re: [GHC] #14847: Inferring dependent kinds for non-recursive types

2 Dec 2018

      #14847: Inferring dependent kinds for non-recursive types
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        Reporter:  simonpj           |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.2.2
      Resolution:                    |             Keywords:  TypeInType
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
  https://ghc.haskell.org/trac/ghc/wiki/GhcKinds/KindInference|
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Comment (by RyanGlScott):

 I think commit 2257a86daa72db382eb927df12a718669d5491f8 (`Taming the Kind
 Inference Monster`) fixed this ticket, since the following now compiles
 after that commit:

 {{{#!hs
 {-# LANGUAGE GADTs #-}
 {-# LANGUAGE TypeFamilies #-}
 {-# LANGUAGE TypeInType #-}
 module Bug where

 data Proxy k (a :: k) = MkProxy
 data Proxy2 k a = MkP (Proxy k a)

 data Proxy2' k a where
   MkP' :: Proxy k a -> Proxy2' k a

 data T a where
   T :: Int -> T Bool

 type family F a where
   F Int = True
   F _   = False
 }}}

-- 
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14847#comment:3
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