[GHC] #8704: Use GHC.Exts.build in randoms, randomRs to achieve fusion

[GHC]

#8704: Use GHC.Exts.build in randoms, randomRs to achieve fusion
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       Reporter:  ion1              |             Owner:
           Type:  feature request   |            Status:  new
       Priority:  normal            |         Milestone:
      Component:  libraries/random  |           Version:  7.6.3
       Keywords:  fusion            |  Operating System:  Unknown/Multiple
   Architecture:  Unknown/Multiple  |   Type of failure:  None/Unknown
     Difficulty:  Unknown           |         Test Case:
     Blocked By:                    |          Blocking:
Related Tickets:  #4218             |
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 randoms, randomRs could take advantage of list fusion.

 A commit is attached for consideration.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8704>
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