[GHC] #10598: DeriveAnyClass and GND don't work well together

[GHC]

#10598: DeriveAnyClass and GND don't work well together
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        Reporter:  osa1              |                Owner:  RyanGlScott
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.2.1
       Component:  Compiler          |              Version:  7.11
      Resolution:                    |             Keywords:  Generics
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by oerjan):

 That magic somewhat disturbs me, especially since it means a type synonym
 is not equivalent to its expansion. But if you think it's better than
 (backwards-compatibly) extending the parser to reuse keywords... (I guess
 `default` is a bit of a stretch anyway.)

 In any case, you should also decide how to annotate a `class` definition,
 which is where I actually suggested a pragma. (I think this feature is an
 important part of this: E.g. I think `mtl` classes are almost always used
 with newtype deriving while `aeson` uses generics, and the libraries
 should be able to specify this.)

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10598#comment:24>
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