[GHC] #7545: Type variable capture in InstanceSigs message

[GHC]

#7545: Type variable capture in InstanceSigs message
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    Reporter:  Feuerbach         |       Owner:                             
        Type:  bug               |      Status:  merge                      
    Priority:  normal            |   Milestone:                             
   Component:  Compiler          |     Version:  7.6.1                      
    Keywords:                    |          Os:  Unknown/Multiple           
Architecture:  Unknown/Multiple  |     Failure:  None/Unknown               
  Difficulty:  Unknown           |    Testcase:  typecheck/should_fail/T7545
   Blockedby:                    |    Blocking:                             
     Related:                    |  
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Changes (by simonpj):

  * status:  new => merge
  * difficulty:  => Unknown
  * testcase:  => typecheck/should_fail/T7545


Comment:

 Good point, thank you.  Now we get
 {{{
 T7545.hs:8:9:
     Method signature does not match class; it should be
       f :: forall b1. (a -> b) -> b1
     In the instance declaration for `C (a -> b)'
 }}}
 Merge to 7.6 if it's easy.

 Simon

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7545#comment:2>
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