[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:  strings
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, #9719                      |
       Wiki Page:                    |
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Comment (by phadej):

 Replying to [comment:74 jscholl]:

 I have been trying to write something similar down in https://github.com
 /ghc-proposals/ghc-proposals/compare/master...phadej:bytearray-literals

 It has a different syntax, which I think makes more sense than double-
 hash.

 Ben have given some comments already (they are inline in proposal text, so
 I remember them). He is worried about ByteArray#s code size, and I'm
 proposing similar "let's rewrite them to Addr# when possible" approach.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/5218#comment:83>
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