[GHC] #11977: ghc doesn't agree with its own inferred pattern type

GHC ghc-devs at haskell.org
Thu May 19 07:43:31 UTC 2016


#11977: ghc doesn't agree with its own inferred pattern type
-------------------------------------+-------------------------------------
        Reporter:  Iceland_jack      |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.1
      Resolution:                    |             Keywords:
                                     |  PatternSynonyms
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 Iceland_jack):

 No quantification needed if returning a type synonym:

 {{{#!hs
 type Arr = (->)

 pattern App :: b -> Arr Char b
 pattern App b <- (($ 'a') -> b)
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11977#comment:9>
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