[GHC] #3220: type variables appearing only in type equality constraints are not generalized

[GHC]

#3220: type variables appearing only in type equality constraints are not
generalized
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    Reporter:  guest                    |        Owner:                  
        Type:  bug                      |       Status:  closed          
    Priority:  normal                   |    Milestone:  6.12.1          
   Component:  Compiler (Type checker)  |      Version:  6.10.2          
    Severity:  normal                   |   Resolution:  fixed           
    Keywords:                           |   Difficulty:  Unknown         
    Testcase:  T3220                    |           Os:  Unknown/Multiple
Architecture:  Unknown/Multiple         |  
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Changes (by chak):

  * testcase:  => T3220
  * status:  new => closed
  * resolution:  => fixed

Comment:

 This problem has already been fixed in the HEAD.  I added the example
 (slightly modified) as a regression test.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/3220#comment:2>
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