anchor.diff:  , src ? fetchurl { url = "mirror://hackage/${pname}-${version}.tar.gz"; inherit sha256; }
   , buildDepends ? [], setupHaskellDepends ? [], libraryHaskellDepends ? [], executableHaskellDepends ? []
   , buildTarget ? ""
  -, buildTools ? [], libraryToolDepends ? [], executableToolDepends ? [], testToolDepends ? []
  +, buildTools ? [], libraryToolDepends ? [], executableToolDepends ? [], testToolDepends ? [], benchToolDepends ? []
   , configureFlags ? []
   , description ? ""
   , doCheck ? !isCross && (stdenv.lib.versionOlder "7.4" ghc.version)
  
positive.code:   isSystemPkg = x: !isHaskellPkg x;
  
    allPkgconfigDepends = pkgconfigDepends ++ libraryPkgconfigDepends ++ executablePkgconfigDepends ++
                          optionals doCheck testPkgconfigDepends;
  
    propagatedBuildInputs = buildDepends ++ libraryHaskellDepends ++ executableHaskellDepends;
    otherBuildInputs = extraLibraries ++ librarySystemDepends ++ executableSystemDepends ++ setupHaskellDepends ++
                       buildTools ++ libraryToolDepends ++ executableToolDepends ++
                       optionals (allPkgconfigDepends != []) ([pkgconfig] ++ allPkgconfigDepends) ++
                       optionals doCheck (testDepends ++ testHaskellDepends ++ testSystemDepends ++ testToolDepends) ++
                       optionals doBench benchDepends;
    allBuildInputs = propagatedBuildInputs ++ otherBuildInputs;
  
    haskellBuildInputs = stdenv.lib.filter isHaskellPkg allBuildInputs;
  
negative.code: # TODO Do we care about haddock when cross-compiling?
  , doHaddock ? !isCross && (!stdenv.isDarwin || stdenv.lib.versionAtLeast ghc.version "7.8")
  , passthru ? {}
  , pkgconfigDepends ? [], libraryPkgconfigDepends ? [], executablePkgconfigDepends ? [], testPkgconfigDepends ? [], benchPkgconfigDepends ? []
  , testDepends ? [], testHaskellDepends ? [], testSystemDepends ? []
  , benchDepends ? [], benchHaskellDepends ? [], benchSystemDepends ? []
  , testTarget ? ""
  , broken ? false
  , preCompileBuildDriver ? "", postCompileBuildDriver ? ""
  