[GHC] #2029: Add --with-libedit flag to the readline package

[GHC]

#2029: Add --with-libedit flag to the readline package
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    Reporter:  judah              |       Owner:          
        Type:  proposal           |      Status:  new     
    Priority:  normal             |   Milestone:  Not GHC 
   Component:  libraries (other)  |     Version:          
    Severity:  normal             |    Keywords:          
  Difficulty:  Unknown            |    Testcase:          
Architecture:  Multiple           |          Os:  Multiple
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 It would be useful for the readline package to support compiling against
 the libedit library (which provides a subset of the readline APIs):
  - libedit is available by default on OS X.
  - since libedit is BSD-licensed, there are no problems statically linking
 ghc with it.  (This may be useful on Windows.)

 I propose adding a `--with-libedit` flag to the readline autoconf script.
 Without that flag, the package will behave exactly as before, refusing to
 link against libedit.  With that flag, the following behavior occurs:
  - `GNUreadline.framework` (OS X - only) is ignored, if present
  - We try to link with -lreadline, and don't fail if readline is actually
 libedit.
  - If it is libedit, we #ifdef out all of the functions not supported by
 libedit.  (these are generally low-level APIs not needed by most
 applications, including `ghci`.)  Otherwise, if we're linking against GNU
 readline, we support all the available APIs.

 Suggested deadline: Jan. 23, 2008.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/2029>
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