[GHC] #16128: Pattern match checker should shortcut on simple cases

[GHC]

#16128: Pattern match checker should shortcut on simple cases
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        Reporter:  gbaz              |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.6.3
      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):

 > It seems to me that in a case like this, GHC should be able to just
 check that there are no duplicate strings

 I agree that such a simple use-case should not make the pattern match
 checker have a heart attack.

 The pattern-match checker badly needs someone to love it.  It's basically
 in quite good shape, with a published paper to explain how it works.  But
 it suffers from having no active maintainer -- except the ever-energetic
 Ryan S, who has many other things on his radar.

 Who would like to do this?  Many people would thank you!  See
 [wiki:PatternMatchCheck] for a list of open tickets.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/16128#comment:2>
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