[GHC] #15743: Nail down the Required/Inferred/Specified story

[GHC]

#15743: Nail down the Required/Inferred/Specified story
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        Reporter:  simonpj           |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.6.1
      Resolution:                    |             Keywords:
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 simonpj):

 But, to be clear, you could still give an explicit kind signature to `k`
 (at least, when we have explicit kind signatures) thus
 {{{
 T :: forall k (c::k) -> forall (d::k). forall (a::Proxy c) (b :: Proxy d)
 -> SimilarKind a b -> Type
 }}}
 Given that signature, we should accept the declaration.

 So, even if we reject under (1) we have a route accepting it -- and I
 think it's arguable that if you need funny interleaving then it's a good
 thing to write the signature.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15743#comment:10>
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