[GHC] #10653: PatternSynonyms should be imported/exported as part of the wildcard notation

[GHC]

#10653: PatternSynonyms should be imported/exported as part of the wildcard
notation
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        Reporter:  gridaphobe        |                   Owner:
            Type:  feature request   |                  Status:  new
        Priority:  normal            |               Milestone:  7.12.1
       Component:  Compiler          |                 Version:  7.11
      Resolution:                    |                Keywords:  pattern
Operating System:  Unknown/Multiple  |  synonyms
 Type of failure:  None/Unknown      |            Architecture:
      Blocked By:                    |  Unknown/Multiple
 Related Tickets:                    |               Test Case:
                                     |                Blocking:
                                     |  Differential Revisions:
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Comment (by gridaphobe):

 I would argue that `P` belongs to whatever type `Tree` constructs (but not
 `Maybe`), and that `Q` belongs to pairs.

 More generally,
 https://downloads.haskell.org/~ghc/latest/docs/html/users_guide/syntax-
 extns.html#idp23521760 says that pattern synonyms have a type `C => t1 ->
 t2 -> ... -> t`; I would argue that a pattern synonym belongs to the
 outermost type constructor of `t`.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10653#comment:2>
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