[Hackage] #390: add cabal unpack command

[Hackage]

#390: add cabal unpack command
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  Reporter:  duncan              |        Owner:       
      Type:  enhancement         |       Status:  new  
  Priority:  normal              |    Milestone:       
 Component:  cabal-install tool  |      Version:       
  Severity:  normal              |     Keywords:       
Difficulty:  normal              |   Ghcversion:  6.8.3
  Platform:                      |  
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 It'd be handy to be able to `cabal unpack` a package name. It would be
 useful for users to inspect or modify packages.

 {{{
 $ cabal unpack blah
 }}}

 It would just unpack the cached tarball for that package into the current
 directory (which of course always creates a sub-directory). It should
 accept either a versioned or unversioned package name.

 If the package has not been fetched yet then cabal should probably fetch
 it.

-- 
Ticket URL: <http://hackage.haskell.org/trac/hackage/ticket/390>
Hackage <http://haskell.org/cabal/>
Hackage: Cabal and related projects