[GHC] #14288: ScopedTypeVariables with nested foralls broken since 8.0.2

[GHC]

#14288: ScopedTypeVariables with nested foralls broken since 8.0.2
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        Reporter:  MikolajKonarski   |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler (Type    |              Version:  8.2.1
  checker)                           |
      Resolution:                    |             Keywords:
Operating System:  Linux             |         Architecture:  x86_64
 Type of failure:  GHC rejects       |  (amd64)
  valid program                      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by MikolajKonarski):

 In this rare case I have no preference. I assumed this is a bug, because
 it suddenly changed in 8.0.2. The current version indeed makes sense,
 e.g., if one wants different variables to be scoped differently. Are we
 sure that anything one can write with many foralls can be written with one
 forall? No edge cases with line-breaks, kinds, etc.? If so, perhaps that's
 a good thing to write in the manual as well. Thank you for the feedback
 and for the patch. You, guys, rock.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14288#comment:4>
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