[GHC] #16009: Deprecate `optional` from Text.ParserCombinators.ReadP

[GHC]

#16009: Deprecate `optional` from Text.ParserCombinators.ReadP
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        Reporter:  dbaynard          |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:  8.10.1
       Component:  libraries/base    |              Version:  8.6.2
      Resolution:                    |             Keywords:  Applicative,
                                     |  Parsers, ReadP
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  Other             |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by dbaynard):

 This is currently blocked on a decision (from the core libraries
 committee?) on how to proceed — either to take it up (and begin the
 deprecation process for `optional`, to propose a way to take it to the
 wider community (a process I'm happy to lead), or to dismiss as wontfix.

 Whatever the case, I would like to begin the process as soon as possible;
 perhaps even beginning deprecation in the next major release. It seems
 like this would languish here, otherwise.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/16009#comment:3>
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