Re: [GHC] #13640: Core lint error with deferred type holes

2 May 2017

      #13640: Core lint error with deferred type holes
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        Reporter:  Iceland_jack      |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.0.1
      Resolution:                    |             Keywords:
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 RyanGlScott):

 FWIW, I can't reproduce this error with GHC 8.0.2, 8.2.1, or HEAD:

 {{{
 $ /opt/ghc/8.2.1/bin/ghci Bug.hs
 GHCi, version 8.2.0.20170427: http://www.haskell.org/ghc/  :? for help
 Loaded GHCi configuration from /home/rgscott/.ghci
 [1 of 1] Compiling Main             ( Bug.hs, interpreted )

 Bug.hs:12:22: error:
     • Variable not in scope:
         (.)
           :: (f0 a c0 -> f0 b c0)
              -> ((a0 -> b0) -> f1 a0 -> f1 b0) -> f a c -> f b d
     • Perhaps you want to remove ‘.’ from the explicit hiding list
       in the import of ‘Prelude’ (Bug.hs:3:1-27).
    |
 12 | bimap' f g = map2' f . map'
    |
 }}}

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Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13640#comment:2
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