[GHC] #14773: MultiWayIf makes it easy to write partial programs that are not catched by -Wall

[GHC]

#14773: MultiWayIf makes it easy to write partial programs that are not catched by
-Wall
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        Reporter:  SimonHengel       |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.2.2
      Resolution:                    |             Keywords:
                                     |  PatternMatchWarnings
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by simonpj):

 The pattern-match overlap checker can do some simple things with guards,
 if memory serves; but it would indeed need a new entry point.

 At the moment we lack anyone with the time and inclination to pay
 attention to the pattern-match overlap checker.  There's a great paper
 about it, but the actual implementation needs love and care.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14773#comment:4>
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