[GHC] #6022: GHC infers over-general types

[GHC]

#6022: GHC infers over-general types
---------------------------------+------------------------------------------
    Reporter:  simonpj           |       Owner:                  
        Type:  bug               |      Status:  new             
    Priority:  high              |   Milestone:  7.6.2           
   Component:  Compiler          |     Version:  7.4.1           
    Keywords:                    |          Os:  Unknown/Multiple
Architecture:  Unknown/Multiple  |     Failure:  None/Unknown    
  Difficulty:  Unknown           |    Testcase:                  
   Blockedby:                    |    Blocking:                  
     Related:                    |  
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Comment(by maeder):

 Why is this not Haskell 98? Well, hugs rejects this:

 {{{
 - Cannot infer instance
 *** Instance   : Num ([a] -> a)
 *** Expression : f
 }}}

 But I don't know why, it works with "hugs -98". I cannot make ghc reject
 it, so ghc does not support Haskell 98!

 In any case, I agree with "carter" that it should not be rejected (by
 default). If you ignore
 warnings like "no type signature" it is your own fault!

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/6022#comment:4>
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