anchor.diff:  #
   #  xbase = callPackage ../development/libraries/xbase { };
   #
  -#  xcb-util-cursor = xorg.xcbutilcursor;
   #  xcb-util-cursor-HEAD = callPackage ../development/libraries/xcb-util-cursor/HEAD.nix { };
   #
   #  xdo = callPackage ../tools/misc/xdo { };
  
positive.code: #  xchainkeys = callPackage ../tools/X11/xchainkeys { };
  #
  #  xchm = callPackage ../applications/misc/xchm { };
  #
  #  inherit (xorg) xcompmgr;
  #
  #  xdaliclock = callPackage ../tools/misc/xdaliclock {};
  #
  
negative.code: #  freepv = callPackage ../applications/graphics/freepv { };
  #
  #  xfontsel = callPackage ../applications/misc/xfontsel { };
  #
  #  freerdp = callPackage ../applications/networking/remote/freerdp {
  #    ffmpeg = ffmpeg_1;
  