Re: [GHC] #12553: Reference kind in a type instance declaration defined in another instance declaration

30 Aug 2016

      #12553: Reference kind in a type instance declaration defined in another instance
declaration
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        Reporter:  Iceland_jack      |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.0.1
      Resolution:                    |             Keywords:
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 Iceland_jack):

 It seems to work by ''un-''associating them from `Syntactic`

 {{{#!hs
 type family   Domain a :: Sig u -> Type
 type instance Domain (AST dom (Full a)) = dom

 type family   Internal (a :: Type) :: k
 type instance Internal (AST dom (Full a)) = a
 }}}

 and `instance Syntactic (AST dom (Full a))` compiles.

 Is there some way to get them to compile while associated?

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Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12553#comment:3
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