[GHC] #14107: Implement Semigroup and Monoid instances for the ST monad

[GHC]

#14107: Implement Semigroup and Monoid instances for the ST monad
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        Reporter:  plato             |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Core Libraries    |              Version:  8.2.1
      Resolution:                    |             Keywords:  newcomer
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by RyanGlScott):

 1. Yes, I'd add `@since: 4.11.0.0`, since that will be the next major
 version of `base`.
 2. If it passes `./validate`, then I'd say it works!

    Do note that when you submit a patch via
 [https://phabricator.haskell.org/ Phabricator], the Harbormaster CI
 machines will also run `./validate` against your changes as an additional
 sanity-check.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14107#comment:4>
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