[GHC] #1835: Provide information of the instance environment

[GHC]

#1835: Provide information of the instance environment
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  Reporter:  guest             |          Owner:  igloo           
      Type:  feature request   |         Status:  patch           
  Priority:  normal            |      Milestone:  _|_             
 Component:  Template Haskell  |        Version:  6.8.1           
Resolution:                    |       Keywords:                  
  Testcase:                    |      Blockedby:                  
Difficulty:  Unknown           |             Os:  Unknown/Multiple
  Blocking:                    |   Architecture:  Unknown/Multiple
   Failure:  None/Unknown      |  
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Comment(by illissius):

 Just having isClassInstance fulfills my immediate needs; I don't know what
 I'll want or need in the future. If I could, I'd like to have a pony and
 the ability to map in the reverse direction, i.e. from types to the
 classes they're instances of. (But presumably that can also be added
 separately later.) Thanks for implementing this.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/1835#comment:22>
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