[GHC] #10498: "if ... then \case -> else ..." causes a "missing else clause" error

[GHC]

#10498: "if ... then \case -> else ..." causes a "missing else clause" error
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        Reporter:  dramforever       |                   Owner:
            Type:  bug               |                  Status:  new
        Priority:  normal            |               Milestone:
       Component:  Compiler          |                 Version:  7.10.1
  (Parser)                           |                Keywords:
      Resolution:                    |            Architecture:
Operating System:  Unknown/Multiple  |  Unknown/Multiple
 Type of failure:  Other             |               Test Case:
      Blocked By:                    |                Blocking:
 Related Tickets:                    |  Differential Revisions:
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Comment (by dramforever):

 I ran into this in another more complex program yesterday. It took me 15
 mins to find out the real cause of the error.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10498#comment:1>
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