[GHC] #5927: A type-level "implies" constraint on Constraints

[GHC]

#5927: A type-level "implies" constraint on Constraints
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        Reporter:  illissius         |                Owner:  (none)
            Type:  feature request   |               Status:  closed
        Priority:  normal            |            Milestone:
       Component:  Compiler (Type    |              Version:  7.4.1
  checker)                           |             Keywords:
      Resolution:  duplicate         |  QuantifiedConstraints
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #2893             |  Differential Rev(s):
       Wiki Page:                    |
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Changes (by RyanGlScott):

 * status:  new => closed
 * resolution:   => duplicate
 * related:   => #2893


Comment:

 The "`Implies`" in {{{(c `Implies` Show)}}} is the `=>` in the quantified
 constraint `(c => Show)`. Quantified constraints also allow you to write
 `forall a. Monoid a`.

 Or, to put things another way, this is a duplicate of #2893, which tracks
 the implementation of `QuantifiedConstraints`. I'll close this ticket in
 favor of that one.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/5927#comment:30>
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