anchor.diff:      platforms = stdenv.lib.platforms.linux;
     };
   
  -  # TODO: requires a comment as to what it does and why it is needed.
  -  passthru = {
  -    corePackages = [
  -       [ "Cabal" "1.8.0.2" ]
  -       [ "array" "0.3.0.0" ]
  -       [ "base" "3.0.3.2" ]
  -       [ "base" "4.2.0.0" ]
  -       [ "bin-package-db" "0.0.0.0" ]
  -       [ "bytestring" "0.9.1.5" ]
  -       [ "containers" "0.3.0.0" ]
  -       [ "directory" "1.0.1.0" ]
  -       [ "dph-base" "0.4.0" ]
  -       [ "dph-par" "0.4.0" ]
  -       [ "dph-prim-interface" "0.4.0" ]
  -       [ "dph-prim-par" "0.4.0" ]
  -       [ "dph-prim-seq" "0.4.0" ]
  -       [ "dph-seq" "0.4.0" ]
  -       [ "extensible-exceptions" "0.1.1.1" ]
  -       [ "ffi" "1.0" ]
  -       [ "filepath" "1.1.0.3" ]
  -       [ "ghc" "6.12.1" ]
  -       [ "ghc-binary" "0.5.0.2" ]
  -       [ "ghc-prim" "0.2.0.0" ]
  -       [ "haskell98" "1.0.1.1" ]
  -       [ "hpc" "0.5.0.4" ]
  -       [ "integer-gmp" "0.2.0.0" ]
  -       [ "old-locale" "1.0.0.2" ]
  -       [ "old-time" "1.0.0.3" ]
  -       [ "pretty" "1.0.1.1" ]
  -       [ "process" "1.0.1.2" ]
  -       [ "random" "1.0.0.2" ]
  -       [ "rts" "1.0" ]
  -       [ "syb" "0.1.0.2" ]
  -       [ "template-haskell" "2.4.0.0" ]
  -       [ "time" "1.1.4" ]
  -       [ "unix" "2.4.0.0" ]
  -       [ "utf8-string" "0.3.4" ]
  -    ];
  -  };
   }
  
positive.code: {stdenv, fetchurl, ghc, perl, gmp, ncurses}:
  
  stdenv.mkDerivation rec {
    version = "6.13.20100917";
    
    name = "ghc-${version}";
    
  
negative.code:   homepage = "http://haskell.org/ghc";
  
    src = fetchurl {
      url = "${homepage}/dist/${label}/${name}-src.tar.bz2";
      sha256 = "18jbw5na4v8v2vzswbi8xfd73mx8zv1diym0bg5bns5337q76lzi";
    };
  
    buildInputs = [ghc perl gmp ncurses];
  