[GHC] #15119: Program involving existentials and type class constraint gets rejected

[GHC]

#15119: Program involving existentials and type class constraint gets rejected
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        Reporter:  sgraf             |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler (Type    |              Version:  8.2.2
  checker)                           |
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  GHC rejects       |  Unknown/Multiple
  valid program                      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by sgraf):

 > `Proxy`

 Well, that's what I tried to avoid in this example. There's probably no
 way to get what I want using only `-XTypeApplications`, right? I was the
 one asking the SO question which boils down to asking for a System Fw
 style Big lambda.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15119#comment:2>
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