[GHC] #9043: Add missing type class instances for data types in GHC.Generics

[GHC]

#9043: Add missing type class instances for data types in GHC.Generics
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        Reporter:  ocharles          |            Owner:  dreixel
            Type:  feature request   |           Status:  patch
        Priority:  normal            |        Milestone:
       Component:  libraries/base    |          Version:  7.8.2
      Resolution:                    |         Keywords:
Operating System:  Unknown/Multiple  |     Architecture:  Unknown/Multiple
 Type of failure:  None/Unknown      |       Difficulty:  Unknown
       Test Case:                    |       Blocked By:
        Blocking:                    |  Related Tickets:
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Comment (by ocharles):

 Alright, I've responded to some comments and added more instances. Could
 people please have another look? I wrote out Data instances, but I have
 never actually used Data.Data, so I may have got that wrong. Is it
 possible to write Data instances for (:+:) and friends? My initial attempt
 was no, but I may have missed something. Latest code is at
 https://github.com/ocharles/ghc/tree/generics-instances (as before).

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9043#comment:8>
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