[Hackage] #524: support file, directory and url targets for packages and .cabal files

[Hackage]

#524: support file, directory and url targets for packages and .cabal files
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  Reporter:  duncan              |        Owner:         
      Type:  enhancement         |       Status:  new    
  Priority:  normal              |    Milestone:         
 Component:  cabal-install tool  |      Version:  1.6.0.1
  Severity:  normal              |     Keywords:         
Difficulty:  hard (< 1 day)      |   Ghcversion:         
  Platform:                      |  
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 Currently the `cabal` program supports two ways to specify a package. One
 is implicitly to look in the current directory for a .cabal file. The
 other is a package name (actually a dependency) which we look for in the
 current set of repositories.

 We can imagine adding more. We could:
  * specify the file name of a .cabal file, eg to target an unpacked
 package in another directory
  * specify the directory name and look in that directory for a .cabal file
  * specify the file name or url of a `.tar.gz` package

 For example:
 {{{
 cabal list ../some/other/dir/
 cabal info http://code.haskell.org/xmonad/xmonad.cabal
 cabal install http://haskell.org/cabal/dev/Cabal-1.7.2.tar.gz
 cabal install ./demo/
 }}}

 The case `cabal info http://code.haskell.org/xmonad/xmonad.cabal` is very
 much like the `lscabal` program that was uploaded to hackage recently so
 apparently it is useful.

-- 
Ticket URL: <http://hackage.haskell.org/trac/hackage/ticket/524>
Hackage <http://haskell.org/cabal/>
Hackage: Cabal and related projects