[GHC] #11465: Eliminate check_lifted check in TcValidity

[GHC]

#11465: Eliminate check_lifted check in TcValidity
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        Reporter:  simonpj           |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  7.10.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D1807
       Wiki Page:                    |
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Comment (by bgamari):

 Things seem to work about as one would expect with Phab:D1807.

 However, this error could use a bit of work,
 {{{
 λ> :set -XTypeInType -XDataKinds -XKindSignatures -XMagicHash
 λ> import GHC.Exts
 λ> class Eq Char# where (==) = undefined

 <interactive>:3:10: error:
     Unexpected type ‘Char#’
     In the class declaration for ‘Eq’
     A class declaration should have form
       class Eq a where ...
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11465#comment:3>
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