[GHC] #12369: data families shouldn't be required to have return kind *, data instances should

[GHC]

#12369: data families shouldn't be required to have return kind *, data instances
should
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        Reporter:  ekmett            |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:  8.4.1
       Component:  Compiler (Type    |              Version:  8.0.1
  checker)                           |
      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:                    |
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Comment (by Richard Eisenberg <rae@…>):

 In [changeset:"791947db6db32ef7d4772a821a0823e558e3c05b/ghc"
 791947db/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="791947db6db32ef7d4772a821a0823e558e3c05b"
 Refactor tcInferApps.

 With the changes caused by the fix to #12369, it is now clearer
 how to rewrite tcInferApps and friends. This should change no
 behavior, but it does clean up a nasty corner of the type checker.
 This commit also removes some uses of substTyUnchecked.
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12369#comment:13>
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