[GHC] #9699: TH function to list names in scope

[GHC]

#9699: TH function to list names in scope
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              Reporter:              |            Owner:
  MikeIzbicki                        |           Status:  new
                  Type:  feature     |        Milestone:
  request                            |          Version:  7.8.3
              Priority:  normal      |         Keywords:
             Component:  Template    |     Architecture:  Unknown/Multiple
  Haskell                            |       Difficulty:  Unknown
            Resolution:              |       Blocked By:
      Operating System:              |  Related Tickets:
  Unknown/Multiple                   |
       Type of failure:              |
  None/Unknown                       |
             Test Case:              |
              Blocking:              |
Differential Revisions:              |
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Comment (by simonpj):

 Indeed it would not be hard. I'd be open to patches.

 There are open design questions.  Do you mean "all names in scope"
 (including imported ones)?  There may be a lot of those.  Or just those
 bound in this module?  Or just those bound by nested (non-top-level)
 definitions?

 Moreover, although, say `Data.List.partition` may not be ''lexically'' in
 scope, it's fine to generate a TH program that refers to it, thus:
 {{{
 module Foo where
 import Bar( bar )
 f x = $(bar 5)
 }}}
 where `bar` is a TH function in another module `Bar` where
 `Data.List.partition` is in scope, and `(bar 5)` expands to code
 mentioning `partition`.  So, is `Data.List.partition` "in scope"?

 As ever, getting the specification right (and precise) is a big part of
 the work!

 Simon

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9699#comment:1>
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