[GHC] #13520: instance Alternative ZipList

[GHC]

#13520: instance Alternative ZipList
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        Reporter:  Iceland_jack      |                Owner:  (none)
            Type:  feature request   |               Status:  closed
        Priority:  normal            |            Milestone:  8.4.1
       Component:  libraries/base    |              Version:  8.0.1
      Resolution:  fixed             |             Keywords:  newcomer
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D3416
       Wiki Page:                    |
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Comment (by Iceland_jack):

 Cale from `#haskell` points out the following:

 {{{
 <Cale> Iceland_jack: I think it probably ought to be the one which uses
 Semigroup's (<>) to combine corresponding elements.
 <Cale> Iceland_jack: Then you can recover the instance there by using the
 First semigroup
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13520#comment:8>
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