[GHC] #14349: Semigroup/Monoid instances for System.Exit.ExitCode

[GHC]

#14349: Semigroup/Monoid instances for System.Exit.ExitCode
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        Reporter:  neil.mayhew       |                Owner:  (none)
            Type:  feature request   |               Status:  upstream
        Priority:  low               |            Milestone:
       Component:  libraries/base    |              Version:  8.2.1
      Resolution:                    |             Keywords:
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 nomeata):

 I am not yet convinced. Is this the only sensible `Monoid` instance? Do we
 want to see code that says `returnWith mempty`? Why is leftmost the right
 thing?

 Note that it is verymuch noch like `set -e` because `set -e` *stops* after
 the first error.

 Maybe a named function `anySuccess :: [ExitCode] -> ExitCode` would be a
 better design.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14349#comment:3>
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