[GHC] #8360: panic! (the 'impossible' happened): ... kindFunResult

[GHC]

#8360: panic! (the 'impossible' happened): ... kindFunResult
------------------------------------+-------------------------------------
       Reporter:  2piix             |             Owner:
           Type:  bug               |            Status:  new
       Priority:  normal            |         Milestone:
      Component:  GHCi              |           Version:  7.6.3
       Keywords:                    |  Operating System:  Unknown/Multiple
   Architecture:  Unknown/Multiple  |   Type of failure:  None/Unknown
     Difficulty:  Unknown           |         Test Case:
     Blocked By:                    |          Blocking:
Related Tickets:                    |
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 I got an 'impossible' error on GHCi 7.6.3 after trying to evaluate a type
 for a Yesod value:


 {{{
 *Yesod.Import> :t handlerToWidget
 handlerToWidget :: Monad m => HandlerT site m a -> WidgetT site m a
 *Yesod.Import> :t generateFormPost
 generateFormPost
   :: (RenderMessage (HandlerSite m) FormMessage, MonadHandler m) =>
      (blaze-markup-0.5.1.5:Text.Blaze.Internal.Markup
       -> MForm m (FormResult a, xml))
      -> m (xml, Enctype)
 *Yesod.Import> :t lift
 lift :: (Monad m, MonadTrans t) => m a -> t m a
 *Yesod.Import> :t handlerToWidget . generateFormPost . lift

 <interactive>:1:38:ghc: panic! (the 'impossible' happened)
   (GHC version 7.6.3 for x86_64-unknown-linux):
         kindFunResult
 <<details unavailable>>
 }}}

 Reporting since GHC asked so nicely. :)

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8360>
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