[GHC] #5209: ^C doesn't correctly reset the prompt from within multiline commands in ghci

[GHC]

#5209: ^C doesn't correctly reset the prompt from within multiline commands in
ghci
---------------------------------+------------------------------------------
    Reporter:  dmwit             |       Owner:              
        Type:  bug               |      Status:  new         
    Priority:  normal            |   Component:  Compiler    
     Version:  7.0.3             |    Keywords:              
    Testcase:                    |   Blockedby:              
          Os:  Unknown/Multiple  |    Blocking:              
Architecture:  Unknown/Multiple  |     Failure:  None/Unknown
---------------------------------+------------------------------------------
 Steps to reproduce:

 1. Open ghci.[[BR]]
 2. Start a multiline command with ":{".[[BR]]
 3. Decide multiline commands are overrated, and hit Ctrl-C to
 cancel.[[BR]]

 Observed output:
 {{{
 Prelude> :{
 Prelude|
 Prelude|
 }}}

 Expected output:
 {{{
 Prelude> :{
 Prelude|
 Prelude>
 }}}

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/5209>
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