[GHC] #792: add viewMin/Max

[GHC]

#792: add viewMin/Max
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    Reporter:  jpbernardy      |        Owner:             
        Type:  task            |       Status:  new        
    Priority:  normal          |    Milestone:             
   Component:  libraries/base  |      Version:  6.5        
    Severity:  normal          |     Keywords:  collections
          Os:  Unknown         |   Difficulty:  Unknown    
Architecture:  Unknown         |  
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Have a function to get min/max element, remove it from the collection, and
 tolerate an empty collection (fail in a monad).

 It will probably be added to the Map class.

 refs:
 http://www.haskell.org//pipermail/libraries/2006-June/005446.html
 http://www.eecs.tufts.edu/~rdocki01/docs/edison/Data-Edison-Assoc.html

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Ticket URL: <http://cvs.haskell.org/trac/ghc/ticket/792>
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