[GHC] #11198: TypeInType error message regressions

[GHC]

#11198: TypeInType error message regressions
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        Reporter:  goldfire          |                Owner:  goldfire
            Type:  bug               |               Status:  new
        Priority:  high              |            Milestone:  8.2.1
       Component:  Compiler (Type    |              Version:  7.11
  checker)                           |             Keywords:  TypeInType,
      Resolution:                    |  ErrorMessages
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #11672            |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by goldfire):

 No motion on this, I'm afraid. I'd love to get to this by 8.2, believe me.
 Can't swear to it, as I'm prioritizing the levity polymorphism stuff. I've
 left my work [https://github.com/goldfirere/ghc/tree/irreducible-hetero
 here]. There's a chance that rebasing that patch might just work, given
 the changes to the solver in the meantime. (I gave up because of a solver
 loop, and my memory just barely tells me that I thought at the time that
 the loop wasn't my fault.) I'll at least check this possibility soon.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11198#comment:9>
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