[GHC] #13064: Incorrect redudant imports warning

[GHC]

#13064: Incorrect redudant imports warning
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        Reporter:  phadej            |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.0.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Incorrect         |  Unknown/Multiple
  error/warning at compile-time      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by simonpj):

 Helpful example, thank you.

 Just for context, in comment:12, I guess `Control.Applicative` exports
 `pure` and `<$`.

 * So the use of `<$` needs `import Control.Applicative`
 * The use of `pure` could come from `import Prelude( IO, pure )` or from
 `import Control.Applicative`; but for some reason GHC 8 chooses the
 former, whereas the rules in wiki:Commentary/Compiler/UnusedImports says
 the latter.

 Is that your reasoning?

 Are you saying "I like the rules in
 wiki:Commentary/Compiler/UnusedImports, but they aren't being
 implemented", or are you saying "I'd like different rules"?

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13064#comment:13>
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