[GHC] #5218: Add unpackCStringLen# to create Strings from string literals

[GHC]

#5218: Add unpackCStringLen# to create Strings from string literals
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        Reporter:  tibbe             |                Owner:  thoughtpolice
            Type:  feature request   |               Status:  patch
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  7.0.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Runtime           |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #5877 #10064      |  Differential Rev(s):  Phab:D2443
  #11312                             |
       Wiki Page:                    |
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Comment (by phadej):

 jscholl, I'd like to participate on the proposal, bgamari mentioned above.

 I really think we (= community) should design this properly, as you
 mentioned `Addr#` and `ByteArray#` are confusing. Also Unicode/encodings
 add some complexity. The reward, is that we can close many tickets (at
 least #11312 with "single" change.

 I still try to wrap my head around internals, and my friends' weading is
 in 20 hours, so I'll return to this only next week

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/5218#comment:76>
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