[GHC] #14478: Abstract pattern synonyms (for hsig and hs-boot)

[GHC]

#14478: Abstract pattern synonyms (for hsig and hs-boot)
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        Reporter:  ezyang            |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler (Type    |              Version:  8.2.1
  checker)                           |
      Resolution:                    |             Keywords:  backpack
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 simonpj):

 We also need to know arity because, type system aside, we still need to
 know how many arguments the pattern synonym should be applied to in a
 pattern.  Eg
 {{{
        f (P x)
 vs
        f (P x y)
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14478#comment:2>
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