[GHC] #915: Implement list fusion using streams instead of foldr/build

[GHC]

#915: Implement list fusion using streams instead of foldr/build
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        Reporter:  simonpj  |            Owner:
            Type:  task     |           Status:  closed
        Priority:  normal   |        Milestone:  7.6.1
       Component:           |          Version:  6.8
  libraries/base            |         Keywords:  fusion
      Resolution:  invalid  |     Architecture:  Unknown/Multiple
Operating System:           |       Difficulty:  Project (more than a week)
  Unknown/Multiple          |       Blocked By:
 Type of failure:           |  Related Tickets:
  None/Unknown              |
       Test Case:  N/A      |
        Blocking:           |
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Comment (by duncan):

 We do now have a solution, however the current implementation relies on
 HERMIT. See:

 ''The HERMIT in the Stream -- Fusing Stream Fusion’s concatMap'' by Andrew
 Farmer, Christian Höner zu Sierdissen and Andy Gill.

 http://ittc.ku.edu/~afarmer/concatmap-pepm14.pdf

 See also this summary/commentary: http://blog.ezyang.com/2014/01/pepm14
 -the-hermit-in-the-stream/

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/915#comment:46>
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