[GHC] #11364: Possible type-checker regression in GHC 8.0

[GHC]

#11364: Possible type-checker regression in GHC 8.0
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        Reporter:  hvr               |                Owner:
            Type:  bug               |               Status:  new
        Priority:  highest           |            Milestone:  8.0.1
       Component:  Compiler (Type    |              Version:  7.10.3
  checker)                           |
      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 hvr):

 Changing the type-signature to

 {{{#!hs
 unthrow :: Throws e => proxy e -> (Throws e => a) -> a
 }}}

 In fact makes the code compile... but is this a regression or not? :-)

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11364#comment:1>
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