[GHC] #5277: Clash between RankNTypes and TypeFamilies

[GHC]

#5277: Clash between RankNTypes and TypeFamilies
----------------------------------------+-----------------------------------
  Reporter:  stefan                     |          Owner:                                              
      Type:  bug                        |         Status:  closed                                      
  Priority:  normal                     |      Milestone:                                              
 Component:  Compiler                   |        Version:  7.0.3                                       
Resolution:  invalid                    |       Keywords:  rank-n types, type families, type signatures
  Testcase:                             |      Blockedby:                                              
Difficulty:                             |             Os:  Unknown/Multiple                            
  Blocking:                             |   Architecture:  Unknown/Multiple                            
   Failure:  GHC rejects valid program  |  
----------------------------------------+-----------------------------------

Comment(by stefan):

 Thanks for the quick response. It could well be that my brain's just not
 big enough for this, but I still don't quite get the part where type
 checking only fails *after* one adds the type signature. My apologies for
 the inconvenience, but I would really like to understand the issue there.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/5277#comment:3>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler