[GHC] #11432: Cannot export operator newtype

[GHC]

#11432: Cannot export operator newtype
-------------------------------------+-------------------------------------
        Reporter:  phadej            |                Owner:  skvadrik
            Type:  bug               |               Status:  new
        Priority:  highest           |            Milestone:  8.0.1
       Component:  Compiler          |              Version:  8.0.1-rc1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D1902
       Wiki Page:                    |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"693a54ea7ac6bdd229e0a297fc023d25263077b9/ghc" 693a54e/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="693a54ea7ac6bdd229e0a297fc023d25263077b9"
 Improved error message about exported type operators.

 There is ambiguty between (1) type constructors and (2) data
 constructors in export lists, e.g. '%%' can stand for both of them. This
 ambiguity is resolved in favor of (2).

 If the exported data constructor is not in scope, but type constructor
 with the same name is in scope, GHC should suggest adding 'type' keyword
 to resolve ambiguity in favor of (1) and enabling 'TypeOperators'
 extension.

 The patch only extends the error message.

 See Trac #11432.

 Test Plan: `make test`

 Reviewers: simonpj, bgamari, austin

 Reviewed By: simonpj

 Subscribers: mpickering, thomie, goldfire, kosmikus

 Differential Revision: https://phabricator.haskell.org/D1902

 GHC Trac Issues: #11432
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11432#comment:29>
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