[GHC] #9901: Error message: f is applied to two arguments, but its type has only two (sic)

[GHC]

#9901: Error message: f is applied to two arguments, but its type has only two
(sic)
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        Reporter:  zardoz            |                   Owner:
            Type:  bug               |                  Status:  new
        Priority:  normal            |               Milestone:
       Component:  Compiler (Type    |                 Version:  7.8.3
  checker)                           |                Keywords:
      Resolution:                    |            Architecture:
Operating System:  Unknown/Multiple  |  Unknown/Multiple
 Type of failure:  None/Unknown      |               Test Case:
      Blocked By:                    |                Blocking:
 Related Tickets:                    |  Differential Revisions:
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Comment (by zardoz):

 Sorry, I lost track of this. I’ve attached a program which will reproduce
 this message on GHC 7.8.4. It doesn’t seem to relate to a forgotten do.
 It’s triggered by the wrong type annotation to the value of «preview».

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9901#comment:3>
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