[haskell-platform] #13: Cabal won't track tool dependencies

[haskell-platform]

#13: Cabal won't track tool dependencies
--------------------+-------------------------------------------------------
 Reporter:  dons    |        Owner:  SvenPanne          
     Type:  defect  |       Status:  new                
 Priority:  major   |    Milestone:  Release 2: 2009.1.0
Component:  GLUT    |   Resolution:                     
 Keywords:          |  
--------------------+-------------------------------------------------------
Changes (by claus):

  * owner:  => SvenPanne
  * component:  => GLUT

Comment:

 All of [http://hackage.haskell.org/cgi-bin/hackage-scripts/package/haddock
 haddock], [http://hackage.haskell.org/cgi-bin/hackage-
 scripts/package/happy happy], and [http://hackage.haskell.org/cgi-bin
 /hackage-scripts/package/alex alex] are on hackage.

 Though the peculiarities of GHC Api clients mean that haddock isn't much
 use standalone anymore (it needs to be built with the exact GHC you want
 to use it with, and it needs to be run over all the packages you want to
 include in the platform, in advance).

 I'm not sure why cabal treats applications differently than libraries in
 terms of registering their package info, but as a workaround, one could
 imagine a convention by which every application also provides a library
 with meta-information (the path to the installed executable, as a
 minimum). Similar to the `ghc-paths` package (though ghc itself isn't on
 hackage).

 Something like:
 {{{
 module Application.Haddock where
 path = "<where cabal installed haddock executable>"

 module Application.Happy where
 path = "<where cabal installed happy executable>"

 module Application.Alex where
 path = "<where cabal installed alex executable>"
 }}}
 That would enable tracking by Cabal, as well as support haddock,alex,happy
 clients in figuring out where those executables are. This, in turn, would
 allow to simplify Cabal, which currently has a hardwired list of
 `builtinPrograms` for this purpose.

 I am sure this has been discussed before, but I can't find either thread
 or ticket:-(

-- 
Ticket URL: <http://trac.haskell.org/haskell-platform/ticket/13#comment:1>
haskell-platform <http://trac.haskell.org/haskell-platform>
The Haskell Platform: a comprehensive and robust collection of Haskell libraries