[GHC] #9499: Add -prelude-is flag

[GHC]

#9499: Add -prelude-is flag
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              Reporter:  agibiansky  |            Owner:  agibiansky
                  Type:  feature     |           Status:  new
  request                            |        Milestone:
              Priority:  normal      |          Version:  7.9
             Component:  Compiler    |         Keywords:  flag
            Resolution:              |     Architecture:  Unknown/Multiple
      Operating System:              |       Difficulty:  Easy (less than 1
  Unknown/Multiple                   |  hour)
       Type of failure:              |       Blocked By:
  None/Unknown                       |  Related Tickets:
             Test Case:              |
              Blocking:              |
Differential Revisions:              |
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Changes (by ezyang):

 * differential:  Phab:D171 =>


Comment:

 I'm sorry I'm late to the conversation, but I wanted to remark that with
 GHC HEAD, there is an alternative implementation path to this feature,
 which is reusing the new module renaming support. Essentially, instead of
 saying `-prelude-is`, you can say `-package "base hiding (Prelude)"
 -package "my-prelude (MyPrelude as Prelude)"`. (Well, actually, the
 `hiding` modifier is not supported yet, but it wouldn't be hard to add.)
 Obviously this set of flags is longer, so `-prelude-is` might still be a
 handy shortcut, but an FYI!

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9499#comment:3>
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