[GHC] #7903: Failure to find class instance specified with extra parentheses

[GHC]

#7903: Failure to find class instance specified with extra parentheses
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Reporter:  conal             |          Owner:                  
    Type:  bug               |         Status:  new             
Priority:  normal            |      Component:  Compiler        
 Version:  7.6.3             |       Keywords:                  
      Os:  Unknown/Multiple  |   Architecture:  Unknown/Multiple
 Failure:  None/Unknown      |      Blockedby:                  
Blocking:                    |        Related:                  
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Comment(by parcs):

 Hi Simon,

 Note that changing

 {{{
 instance Eq (((->) a) b)
 }}}

 to

 {{{
 instance Eq (((->) a :: * -> *) b)
 }}}

 causes the error to reappear. And in this case you can't have
 `splitHsAppTys` look through kind signatures as well because then the kind
 signature can't be checked in `tc_hs_type` since it will be discarded.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7903#comment:2>
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