[GHC] #1480: Template Haskell should allow reification of modules

[GHC]

#1480: Template Haskell should allow reification of modules
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        Reporter:  igloo    |            Owner:
            Type:  feature  |           Status:  patch
  request                   |        Milestone:  7.8.1
        Priority:  high     |          Version:  7.7
       Component:           |         Keywords:
  Template Haskell          |     Architecture:  Unknown/Multiple
      Resolution:           |       Difficulty:  Moderate (less than a day)
Operating System:           |       Blocked By:
  Unknown/Multiple          |  Related Tickets:
 Type of failure:           |
  None/Unknown              |
       Test Case:           |
        Blocking:  8398     |
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Changes (by errge):

 * blocking:  8398, 8489 => 8398


Comment:

 Thanks for the review, I'll look into how current usages is handled and
 what is the best way to fix these issues.  I've created another ticket for
 this: #8489 and assigned it to myself.

 In the meantime, by slightly modifying your example, I've confirmed that
 usages always contains the imports, even if they're not used.  So I never
 get less than what I want.  I confirmed this behavior also through the
 source code via this backtrace:
   - [[GhcFile(compiler/deSugar/Desugar.lhs#L167)]]
   - [[GhcFile(compiler/iface/MkIface.lhs#L147)]]
   - [[GhcFile(compiler/iface/MkIface.lhs#L256)]]
   - [[GhcFile(compiler/iface/MkIface.lhs#L921)]]
   - [[GhcFile(compiler/iface/MkIface.lhs#L944)]]


 So for me this patch would already be very useful in 7.8.1, and yes, I'll
 work on fixing the remaining edge case that you've just showed.  If
 everyone agrees, please apply this as-is.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/1480#comment:16>
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