[GHC] #14320: Brackets change meaning of value-constructor type

[GHC]

#14320: Brackets change meaning of value-constructor type
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           Reporter:  nr             |             Owner:  (none)
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:
          Component:  Compiler       |           Version:  8.2.1
  (Type checker)                     |
           Keywords:  GADT,          |  Operating System:  Linux
  existential type                   |
       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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 Some legacy code from GHC 7.x does not compile under 8.0 or 8.2.
 The issue seems to be that I have wrapped brackets around the type
 of a value constructor, and 8.x does not want to see those brackets.

 To try to learn if this change was deliberate, I have searched the release
 notes.  Found nothing.

 I am hoping this is an actual bug, as I would hope to be able to wrap any
 type or term in brackets without changing its meaning (except of course
 for fixity).

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14320>
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