Kind signatures and Type families

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I expect

type family Rep a

and

type family Rep :: * -> *

to be the same, but it seems there is a difference

type family   Rep a
type instance Rep Int  = Char
-- ok

type family   Rep :: * -> *
type instance Rep Int  = Char
-- Expected kind * -> *, but got 'Int' instead

Have I simply stumbled over an Haskell extension bug, or is there some point to this behavior?

1 Answers
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