[GHC] #8489: clean up dependency and usages handling in interface files

[GHC]

#8489: clean up dependency and usages handling in interface files
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        Reporter:  errge             |                Owner:  errge
            Type:  task              |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Template Haskell  |              Version:  7.7
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by mgsloan):

 I don't understand how the explicit imports list of a module would be
 helpful to another module.  I've never grokked the usecase for this.

 I suggest just changing the documentation to indicate that it is a list of
 usages rather than imports, to resolve this.  How's that sound?  Assigning
 this ticket to myself, to implement via documentation.

 Alternatively, this usages information could just get removed.  Worth
 checking if there are uses of it on hackage.  I am considering
 implementing reification of exports
 (https://ghc.haskell.org/trac/ghc/ticket/10391), which is what I think
 most people would want in module reification as that would be quite
 useful.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8489#comment:12>
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