[GHC] #7825: Class used as a type parameter typechecks

[GHC]

#7825: Class used as a type parameter typechecks
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Reporter:  mojojojo          |          Owner:                  
    Type:  bug               |         Status:  new             
Priority:  normal            |      Component:  Compiler        
 Version:  7.6.2             |       Keywords:                  
      Os:  Unknown/Multiple  |   Architecture:  Unknown/Multiple
 Failure:  None/Unknown      |      Blockedby:                  
Blocking:                    |        Related:                  
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 {{{
 class SomeClass a

 someValue :: Maybe (SomeClass a)
 someValue = undefined
 }}}
 This code compiles without any errors.

 The issue originates from [http://stackoverflow.com/questions/15903490
 /why-can-classes-be-used-as-type-parameters-and-what-for this
 stackoverflow question].

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7825>
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