[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:  patch
        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):  Phab:D2280
       Wiki Page:                    |
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Comment (by RyanGlScott):

 Another possibility: we allow the use of multiple `deriving`s after a
 datatype. Something like:

 {{{#!hs
 newtype Foo = Foo Bar
   deriving         (A, B, C)
   deriving builtin (D, E, F)
   deriving newtype (G, H, I)
   deriving default (J, K, L)
 }}}

 Pros: this would be a lot more consistent with the treatment for
 standalone `deriving` declarations. Cons: we'd have to significantly
 rework the way we parse `data`/`newtype` declarations.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10598#comment:37>
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