[GHC] #9151: Recursive default associated types don't kind-generalize properly

[GHC]

#9151: Recursive default associated types don't kind-generalize properly
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        Reporter:  goldfire          |            Owner:
            Type:  bug               |           Status:  new
        Priority:  normal            |        Milestone:
       Component:  Compiler          |          Version:  7.8.2
      Resolution:                    |         Keywords:
Operating System:  Unknown/Multiple  |     Architecture:  Unknown/Multiple
 Type of failure:  None/Unknown      |       Difficulty:  Unknown
       Test Case:                    |       Blocked By:
        Blocking:                    |  Related Tickets:
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Comment (by archblob):

 I think you original assumption still stands, as the current failure
 happens when we try to type-check the type synonym, we don't even get to
 the associated defaults, thus only postponing the type checking of atdefs
 will do no good I think. The failure will still happen at this stage. I
 think the synonym would have to be type checked in a different group,
 after the class declaration and before the atdefs, which will have to be
 checked with other instances as you suggested. Maybe someone else can
 chime in with some ideas about the strategy. Please tell me if my
 assumptions are wrong.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9151#comment:10>
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