[GHC] #10797: Kind-level functional dependencies are not resolved properly

[GHC]

#10797: Kind-level functional dependencies are not resolved properly
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        Reporter:  danilo2           |                   Owner:
            Type:  bug               |                  Status:  new
        Priority:  normal            |               Milestone:
       Component:  Compiler          |                 Version:  7.10.2
      Resolution:                    |                Keywords:
Operating System:  Unknown/Multiple  |            Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |               Test Case:
      Blocked By:                    |                Blocking:
 Related Tickets:                    |  Differential Revisions:
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Comment (by danilo2):

 And one more additional fact. We can implement what I want creating some
 boilerplate. I'm sure there should be way to avoid it (without using
 TemplateHaskell):
 {{{
 class BaseType a b | a -> b where
     baseType :: a -> b

 instance {-# OVERLAPPABLE #-} out ~ (Proxy a) => BaseType (Proxy a) out
 instance {-# OVERLAPPABLE #-} out ~ (Proxy a) => BaseType (Proxy (a t1))
 out
 instance {-# OVERLAPPABLE #-} out ~ (Proxy a) => BaseType (Proxy (a t1
 t2)) out
 instance {-# OVERLAPPABLE #-} out ~ (Proxy a) => BaseType (Proxy (a t1 t2
 t3)) out
 instance {-# OVERLAPPABLE #-} out ~ (Proxy a) => BaseType (Proxy (a t1 t2
 t3 t4)) out
 instance {-# OVERLAPPABLE #-} out ~ (Proxy a) => BaseType (Proxy (a t1 t2
 t3 t4 t5)) out
 ...
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10797#comment:4>
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