[GHC] #10453: \case should trigger auto-multiline mode in ghci

[GHC]

#10453: \case should trigger auto-multiline mode in ghci
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              Reporter:  dmwit       |             Owner:
                  Type:  feature     |            Status:  new
  request                            |         Milestone:
              Priority:  normal      |           Version:  7.10.1
             Component:  Compiler    |  Operating System:  Unknown/Multiple
              Keywords:              |   Type of failure:  None/Unknown
          Architecture:              |        Blocked By:
  Unknown/Multiple                   |   Related Tickets:
             Test Case:              |
              Blocking:              |
Differential Revisions:              |
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 In ghci, most block heralds trigger the multiline mode when :set +m is on.
 However, \case does not (and should). Compare:

 {{{
 Prelude> ($True) (\case
 Prelude|  x -> x
 Prelude| )
 True
 Prelude> ($True) $ \case

 <interactive>:11:11:
     Empty list of alternatives in case expression
       Use EmptyCase to allow this
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10453>
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