anchor.diff:  
     mlt-qt4 = callPackage ../development/libraries/mlt {
       qt = qt4;
  -    SDL = SDL_pulseaudio;
     };
   
     mlt-qt5 = callPackage ../development/libraries/mlt {
       qt = qt5;
  -    SDL = SDL_pulseaudio;
     };
   
     movit = callPackage ../development/libraries/movit { };
  
positive.code:     openglSupport = mesaSupported;
      alsaSupport = (!stdenv.isDarwin);
      x11Support = true;
      pulseaudioSupport = stdenv.isDarwin; # better go through ALSA
  
      # resolve the unrecognized -fpascal-strings option error
      stdenv = if stdenv.isDarwin
        then clangStdenv
        else stdenv;
    };
  
    # Fixes major problems with choppy sound in MLT / Kdenlive / Shotcut
    SDL_pulseaudio = SDL.override { pulseaudioSupport = true; };
  
    SDL_gfx = callPackage ../development/libraries/SDL_gfx { };
  
  
negative.code:   hedgewars = callPackage ../games/hedgewars {
      inherit (haskellPackages) ghc network vector utf8String bytestringShow
        random hslogger dataenc;
    };
  
    hexen = callPackage ../games/hexen { };
  