[GHC] #8185: Change role annotation syntax

[GHC]

#8185: Change role annotation syntax
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        Reporter:           |            Owner:  goldfire
  goldfire                  |           Status:  new
            Type:  feature  |        Milestone:  7.8.1
  request                   |          Version:  7.7
        Priority:  normal   |         Keywords:
       Component:           |     Architecture:  Unknown/Multiple
  Compiler                  |       Difficulty:  Moderate (less than a day)
      Resolution:           |       Blocked By:
Operating System:           |  Related Tickets:
  Unknown/Multiple          |
 Type of failure:           |
  None/Unknown              |
       Test Case:           |
        Blocking:           |
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Comment (by Richard Eisenberg <eir@…>):

 In [changeset:f4046b508a5a71ff2e28f438b30048867dbad428/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="f4046b508a5a71ff2e28f438b30048867dbad428"
 Change role annotation syntax.

 This fixes bugs #8185, #8234, and #8246. The new syntax is explained
 in the comments to #8185, appears in the "Roles" subsection of the
 manual, and on the [wiki:Roles] wiki page.

 This change also removes the ability for a role annotation on type
 synonyms, as noted in #8234.
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8185#comment:14>
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