[GHC] #4879: Deprecate exports

[GHC]

#4879: Deprecate exports
-------------------------------------+-------------------------------------
        Reporter:  basvandijk        |                   Owner:
            Type:  feature request   |                  Status:  new
        Priority:  high              |               Milestone:  7.12.1
       Component:  Compiler          |                 Version:  7.0.1
      Resolution:                    |                Keywords:
Operating System:  Unknown/Multiple  |            Architecture:
 Type of failure:  None/Unknown      |  Unknown/Multiple
      Blocked By:                    |               Test Case:
 Related Tickets:                    |                Blocking:
                                     |  Differential Revisions:  Phab:D638
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Comment (by hvr):

 for the record, the patch still seems to work:

 {{{#!hs
 module M1 ({-# DEPRECATED sort "dont use me" #-}, sort) where

 import Data.List (sort)
 }}}

 {{{#!hs
 import M1 (sort)

 main :: IO ()
 main = print (sort "asdasd")
 }}}

 {{{
 $ ../inplace/bin/ghc-stage2  -Wall --make M2.hs
 [1 of 2] Compiling M1               ( M1.hs, M1.o )
 [2 of 2] Compiling Main             ( M2.hs, M2.o )

 M2.hs:4:15: Warning:
     In the use of ‘sort’
     (imported from M1, but defined in base-4.8.0.0:Data.OldList):
     Deprecated: "dont use me"
 Linking M2 ...
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/4879#comment:21>
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