[GHC] #9778: Namespace collision detection for promoted types

[GHC]

#9778: Namespace collision detection for promoted types
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              Reporter:  crockeea    |            Owner:
                  Type:  feature     |           Status:  new
  request                            |        Milestone:
              Priority:  normal      |          Version:  7.8.3
             Component:  Compiler    |         Keywords:
            Resolution:              |     Architecture:  Unknown/Multiple
      Operating System:              |       Difficulty:  Unknown
  Unknown/Multiple                   |       Blocked By:
       Type of failure:              |  Related Tickets:
  None/Unknown                       |
             Test Case:              |
              Blocking:              |
Differential Revisions:              |
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Comment (by goldfire):

 I could rally behind calling `-fwarn-unticked-promoted-constructors` the
 solution to this problem. I'm -0.5 on including text in any error message
 about `S` the possibility that the user means `'S` -- just seems like
 noise to me. Note that I've changed the name of the warning flag, as
 `implicit` conjures up the wrong associations for me.

 It's interesting to note that I frequently use ticks everywhere in
 presentations about !DataKinds stuff. (I leave off the ticks in my own
 code, though.) I think requiring the ticks makes for a better reader
 experience for folks who are not deep into this. I also think that the
 ticks should be allowed (but not required) in kinds.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9778#comment:8>
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