[GHC] #2893: Implement "Quantified contexts" proposal

[GHC]

#2893: Implement "Quantified contexts" proposal
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        Reporter:  porges            |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:  ⊥
       Component:  Compiler          |              Version:  6.10.1
      Resolution:                    |             Keywords:  proposal
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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Description changed by simonpj:

Old description:

> See: http://haskell.org/haskellwiki/Quantified_contexts
>
> Motivating example is collapsing insomeway-identical classes such as
> Monoid and MonadPlus into a single class (with accompanying functions).

New description:

 See: [wiki:QuantifiedContexts]

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/2893#comment:26>
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