[GHC] #8356: Strangeness with FunDeps

[GHC]

#8356: Strangeness with FunDeps
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        Reporter:  ksf                           |            Owner:
            Type:  bug                           |           Status:
        Priority:  normal                        |  closed
       Component:  Compiler                      |        Milestone:
      Resolution:  fixed                         |          Version:  7.7
Operating System:  Unknown/Multiple              |         Keywords:
 Type of failure:  GHC rejects valid program     |     Architecture:
       Test Case:                                |  Unknown/Multiple
  typecheck/should_fail/tcfail170                |       Difficulty:
        Blocking:                                |  Unknown
                                                 |       Blocked By:
                                                 |  Related Tickets:
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Changes (by simonpj):

 * status:  new => closed
 * testcase:   => typecheck/should_fail/tcfail170
 * resolution:   => fixed


Comment:

 Error message improved.  Here it is for `tcfail170`:
 {{{
 tcfail170.hs:7:10:
     Illegal instance declaration for ?C [p] [q]?
       The coverage condition fails in class ?C?
         for functional dependency: ?a -> b?
       Reason: lhs type ?[p]? does not deternine rhs type ?[q]?
     In the instance declaration for ?C [p] [q]?
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8356#comment:6>
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