[GHC] #12188: Pattern variables bound by PatternGuards are not accessible in where clause

[GHC]

#12188: Pattern variables bound by PatternGuards are not accessible in where clause
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        Reporter:  heisenbug         |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  7.10.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  GHC rejects       |  Unknown/Multiple
  valid program                      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Changes (by heisenbug):

 * failure:  None/Unknown => GHC rejects valid program


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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12188#comment:1>
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