[GHC] #1207: Unnecessary prohibition of unquantified higher-order typeclass constraints

[GHC]

#1207: Unnecessary prohibition of unquantified higher-order typeclass constraints
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 Reporter:  br276 at cam.ac.uk          |          Owner:          
     Type:  bug                      |         Status:  closed  
 Priority:  low                      |      Milestone:          
Component:  Compiler (Type checker)  |        Version:  6.6     
 Severity:  minor                    |     Resolution:  wontfix 
 Keywords:                           |     Difficulty:  Unknown 
 Testcase:                           |   Architecture:  Multiple
       Os:  Multiple                 |  
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Changes (by simonpj):

  * resolution:  => wontfix
  * status:  new => closed

Comment:

 Types like this are allowed in the HEAD, as a result of a recent and non-
 trivial enhancement to type inference I added, called "implication
 constraints".  There is no chance this is going to change in 6.6 though,
 I'm afraid.

 So it's "won't fix" for 6.6 and "already fixed" for the HEAD!

 Simon

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Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/1207>
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