[GHC] #2044: "Can't unify" error in debugger

[GHC]

#2044: "Can't unify" error in debugger
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 Reporter:  r6144   |          Owner:  mnislaih
     Type:  bug     |         Status:  assigned
 Priority:  normal  |      Milestone:  6.8.3   
Component:  GHCi    |        Version:  6.8.2   
 Severity:  normal  |     Resolution:          
 Keywords:          |     Difficulty:  Unknown 
 Testcase:          |   Architecture:  x86     
       Os:  Linux   |  
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Comment (by mnislaih):

 The way I see it, :print is dealing with concrete values here, and a value
 has a factual type. It does not make sense to impose restrictions like
 class predicates or higher rank foralls on the value's type. Thus I
 believe those higher-rank foralls should be dropped.

 If we have a function type on the other hand, the foralls should be
 respected. But :print should not touch the types of function types anyway.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/2044#comment:8>
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