[GHC] #7862: Could not deduce (A) from the context (A, ...)

[GHC]

#7862: Could not deduce (A) from the context (A, ...)
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    Reporter:  alang9                   |       Owner:                           
        Type:  bug                      |      Status:  new                      
    Priority:  normal                   |   Milestone:                           
   Component:  Compiler (Type checker)  |     Version:  7.6.2                    
    Keywords:                           |          Os:  Linux                    
Architecture:  x86_64 (amd64)           |     Failure:  GHC rejects valid program
  Difficulty:  Unknown                  |    Testcase:                           
   Blockedby:                           |    Blocking:                           
     Related:                           |  
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Comment(by simonpj):

 {{{
 commit db07129cfb13a856f31276c76e9e00924835b18e
 Author: Simon Peyton Jones <simonpj at microsoft.com>
 Date:   Thu May 2 17:14:23 2013 +0100

     Eliminate (given) flatten-skolems in favour of user type variables

     See Note [Eliminate flat-skols].  IT wasn't exactly wrong before
     the the error messages are deeply strange.
 }}}

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7862#comment:3>
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