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Fix printing of higher-rank kinds

Witness this GHCi session:

rae:09:18:37 ~/ghc/ghc> ghci -ignore-dot-ghci
GHCi, version 8.0.1: http://www.haskell.org/ghc/  :? for help
Prelude> :set -XTypeInType -XRankNTypes
Prelude> import Data.Kind
Prelude Data.Kind> data Foo :: (* -> *) -> (forall k. k -> *)
Prelude Data.Kind> :info Foo
type role Foo phantom nominal phantom
data Foo (a :: * -> *) k (c :: k)
  	-- Defined at <interactive>:3:1

The output from :info is terrible, treating k as a visible parameter when it isn't.

This is spun off from #13399 (closed) but is not tightly coupled to that ticket.

Trac metadata
Trac field Value
Version 8.0.1
Type Bug
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture
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