anchor.diff:  
     darwin = let
       cmdline = callPackage ../os-specific/darwin/command-line-tools {};
  -    apple-source-releases = import ../os-specific/darwin/apple-source-releases {
  -      inherit stdenv fetchurl pkgs;
  -    };
  +    apple-source-releases = callPackage ../os-specific/darwin/apple-source-releases { };
     in apple-source-releases // rec {
       cctools_cross = callPackage (forceNativeDrv (callPackage ../os-specific/darwin/cctools/port.nix {}).cross) {
         cross = assert crossSystem != null; crossSystem;
  
positive.code:   # The package compositions.  Yes, this isn't properly indented.
    pkgsFun = pkgs: overrides:
      with helperFunctions;
      let
        # on darwin, put os-specific packages first so they can be overridden by the ones
        # defined here (e.g. libiconv)
        defaultScope = if pkgs.stdenv.isDarwin
          then with pkgs.darwin; apple_sdk.frameworks // apple_sdk.libs // pkgs.darwin // pkgs // pkgs.xorg
          else pkgs // pkgs.xorg;
        self = self_ // overrides;
      self_ = with self; helperFunctions // {
  
    # Make some arguments passed to all-packages.nix available
  
negative.code: 
    nodejs-0_10 = callPackage ../development/web/nodejs/v0_10.nix {
      libtool = darwin.cctools;
      inherit (darwin.apple_sdk.frameworks) CoreServices ApplicationServices Carbon Foundation;
    };
  
    nodejs = if stdenv.system == "armv5tel-linux" then
  