[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 simonpj):

 > It's the ability to choose between Addr# or ByteArray#' or (# Int#,
 Addr# #), etc. that matters

 That's a separate issue.  It is indeed what `OverloadedStrings` is for.
 Perhaps we can have a new ticket for it. But we can't talk meaningfully
 about it until we settle the first issue: what are the primitive types and
 operations over them.  There I think we have a preliminary consensus, with
 `B#` = `ByteArray#`.

 Moreover, I think jscholl has a preliminary implementation (comment:74).
 jscholl: would you like to write up your design as a wiki page?  Can you
 share it?

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/5218#comment:93>
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