[GHC] #11825: Pretty printer doesn't display functional dependency with ‘→’

[GHC]

#11825: Pretty printer doesn't display functional dependency with ‘→’
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           Reporter:  Iceland_jack   |             Owner:
               Type:  feature        |            Status:  new
  request                            |
           Priority:  normal         |         Milestone:
          Component:  GHCi           |           Version:  7.10.3
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  None/Unknown
  Unknown/Multiple                   |
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
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 {{{
 % ghci -ignore-dot-ghci
 GHCi, version 8.1.20160117: http://www.haskell.org/ghc/  :? for help
 Prelude> :set -XUnicodeSyntax
 Prelude> import Control.Monad.Free
 Prelude Control.Monad.Free> :set -XUnicodeSyntax
 Prelude Control.Monad.Free> :i MonadFree
 class Monad m =>
       MonadFree (f :: * -> *) (m :: * -> *) | m -> f where
   wrap :: f (m a) -> m a
   default wrap :: (m ~ t n, Control.Monad.Trans.Class.MonadTrans t,
                    MonadFree f n, Functor f) =>
                   f (m a) -> m a
         -- Defined in ‘Control.Monad.Free.Class’
 instance [safe] Functor f => MonadFree f (Free f)
   -- Defined in ‘Control.Monad.Free’
 Prelude Control.Monad.Free>
 }}}

 should be

 {{{

 class Monad m =>
       MonadFree (f :: * -> *) (m :: * -> *) | m → f where
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11825>
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