[GHC] #1333: core lint failures from arrow notation + HPC

[GHC]

#1333: core lint failures from arrow notation + HPC
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    Reporter:  igloo             |        Owner:                                     
        Type:  bug               |       Status:  new                                
    Priority:  high              |    Milestone:  6.14.1                             
   Component:  Compiler          |      Version:  6.7                                
    Keywords:                    |     Testcase:  arrowrun001 arrowrun002 arrowrun003
   Blockedby:                    |   Difficulty:  Unknown                            
          Os:  Unknown/Multiple  |     Blocking:                                     
Architecture:  Unknown/Multiple  |      Failure:  None/Unknown                       
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Comment(by ross):

 I think the problem here is adding these annotations to if, case, etc
 commands, which are not expressions.  It's a bit tricky because commands
 have the same representation (HsExp) as expressions: the distinction comes
 from the context in which they are used.  Commands occur inside proc
 expressions, and can themselves contain expressions.  The way this is
 handled in most traversals of expressions is to pass an environment that
 differs between commands and expressions.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/1333#comment:15>
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