Re: [GHC] #14607: Core Lint error

23 Dec 2017

      #14607: Core Lint error
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        Reporter:  Iceland_jack      |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.2.2
      Resolution:                    |             Keywords:  TypeInType,
                                     |  DeferredTypeErrors
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #14605 #14584     |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Iceland_jack):

 Simplified example

 {{{#!hs
 {-# Language GADTs #-}
 {-# Language GeneralizedNewtypeDeriving #-}
 {-# Language InstanceSigs #-}
 {-# Language KindSignatures #-}
 {-# Language TypeInType #-}

 import Data.Kind

 type Arr a b = (a, b) -> Type

 data LamCons a :: Arr Type Type where
   LamCons :: LamCons a '([a], [a])

 class Mk (app :: Arr Type Type) where
   mk :: app '(a, b)

 instance Mk (LamCons a :: Arr Type Type) where
   mk :: LamCons '(a, b)
   mk = undefined
 }}}

-- 
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14607#comment:2
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