Re: [GHC] #14748: Infer context for Data instance of (data Foo f = Foo (f Bool) (f Int))

1 Feb 2018

      #14748: Infer context for Data instance of (data Foo f = Foo (f Bool) (f Int))
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        Reporter:  Iceland_jack      |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:
      Resolution:                    |             Keywords:
                                     |  QuantifiedConstraints wipT2893,
                                     |  deriving
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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Comment (by RyanGlScott):

 I too am skeptical that there is a robust, systematic way to do what
 you're seeking. I think the intent of
 https://ghc.haskell.org/trac/ghc/ticket/12245#comment:1 was to combine
 quantified constraints with `StandaloneDeriving`, not have the quantified
 constraints be inferred.

-- 
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14748#comment:2
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