[GHC] #8488: Annotations should not distinguish type and value

30 Oct 2013

      #8488: Annotations should not distinguish type and value
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       Reporter:  simonpj           |             Owner:
           Type:  bug               |            Status:  new
       Priority:  normal            |         Milestone:
      Component:  Compiler          |           Version:  7.6.3
       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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 In `HsDecls` we have
 {{{
 data AnnDecl name = HsAnnotation (AnnProvenance name) (Located (HsExpr
 name))

 data AnnProvenance name = ValueAnnProvenance name
                         | TypeAnnProvenance name
                         | ModuleAnnProvenance
 }}}
 And there's now a similar 3-way distinction in Template Haskell `Syntax`:
 {{{
 data AnnTarget = ModuleAnnotation
                | TypeAnnotation Name
                | ValueAnnotation Name
 }}}
 But there's really no need to distinguish between `TypeAnnProvenance` and
 `ValueAnnProvenance` (and similarly in the TH vesrion) because the
 namespace on the `Name` makes that distinction.  So the current story is
 redundant, and hence has silly case where you have a `ValueAnnProvenance`
 on a type constructor.

 Better to collapse the two.  I'm making this a ticket so that people can
 comment.  I hope that Gergely may be able to do it as part of his
 TH/annotation work.

--
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/8488
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