[GHC] #11129: Nested TH not allowed in declarations

[GHC]

#11129: Nested TH not allowed in declarations
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           Reporter:  andrewthad     |             Owner:
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:
          Component:  Compiler       |           Version:  7.10.2
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  None/Unknown
  Unknown/Multiple                   |
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
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 I tried to do the following with the `singletons` and `derive` libraries:

 {{{#!hs
 $(singletons [d|
   data CrudRoute = AddR | EditR | DeleteR | ViewR
     deriving (Eq,Ord,Enum,Bounded,Show)
   data MyRoute = UsersR | ProfileR | RenameR | DogR CrudRoute
     deriving (Eq,Ord,Show)
   $( derive makeEnum ''MyRoute )
   |])
 }}}

 GHC fails with the following error message:

 Splices within declaration brackets not (yet) handled by Template Haskell

 Here is the github issue where this originated:
 https://github.com/goldfirere/singletons/issues/135#issuecomment-158936027

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11129>
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