[GHC] #4426: Simplify the rules for implicit quantification

[GHC]

#4426: Simplify the rules for implicit quantification
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        Reporter:  simonpj           |            Owner:
            Type:  feature request   |           Status:  new
        Priority:  low               |        Milestone:  7.6.2
       Component:  Compiler          |          Version:  6.12.3
      Resolution:                    |         Keywords:
Operating System:  Unknown/Multiple  |     Architecture:  Unknown/Multiple
 Type of failure:  None/Unknown      |       Difficulty:  Unknown
       Test Case:                    |       Blocked By:
        Blocking:                    |  Related Tickets:  #7880
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Changes (by monoidal):

 * difficulty:   => Unknown
 * related:   => #7880


Comment:

 See also comments at #7880. This change is not hard (I had a very rough
 sketch that detected ~4 missing quantifier errors in GHC tree) but it's
 too late for 7.8. Maybe I'll do it such that 7.10 will give a warning and
 7.12 an error.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/4426#comment:6>
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