[GHC] #2360: More information in occurs check message

[GHC]

#2360: More information in occurs check message
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    Reporter:  ajd              |        Owner:         
        Type:  feature request  |       Status:  new    
    Priority:  normal           |    Milestone:         
   Component:  Compiler         |      Version:  6.8.2  
    Severity:  normal           |   Resolution:         
    Keywords:                   |     Testcase:         
Architecture:  Unknown          |           Os:  Unknown
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Changes (by claus):

 * cc: claus (added)

Comment:

 Perhaps the issue isn't specific to occurs check messages? See my comments
 on #1928.

 Even in the trivial example given here, it would help to have the types
 for `foo`'s rhs and `foo`'s lhs/signature in the message (`a -> a` vs `[a]
 -> a`), to provide context for the type error.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/2360#comment:1>
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