[GHC] #9636: Function with type error accepted

[GHC]

#9636: Function with type error accepted
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              Reporter:  augustss    |            Owner:
                  Type:  bug         |           Status:  new
              Priority:  normal      |        Milestone:
             Component:  Compiler    |          Version:  7.8.3
            Resolution:              |         Keywords:
      Operating System:              |     Architecture:  Unknown/Multiple
  Unknown/Multiple                   |       Difficulty:  Unknown
       Type of failure:              |       Blocked By:
  None/Unknown                       |  Related Tickets:
             Test Case:              |
              Blocking:              |
Differential Revisions:              |
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Comment (by dreixel):

 I don't see why `T Bool` is "not a type". If you really want something
 like that, you should index `T` over a closed kind:

 {{{
 {-# LANGUAGE DataKinds, TypeFamilies #-}

 data Un = TInt

 type family T (a :: Un) :: * where
   T TInt = ()
 }}}

 Now it's clear that `T Bool` is indeed not a type, and gives rise to a
 kind error.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9636#comment:4>
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