anchor.diff:  { stdenv, fetchurl, pkgconfig, python, gstreamer, gobjectIntrospection
   , orc, alsaLib, libXv, pango, libtheora
  -, cdparanoia, libvisual
  +, cdparanoia, libvisual, libintlOrEmpty
   }:
   
   stdenv.mkDerivation rec {
  
positive.code:     description = "Base plugins and helper libraries";
      homepage = "http://gstreamer.freedesktop.org";
      license = stdenv.lib.licenses.lgpl2Plus;
      platforms = stdenv.lib.platforms.linux;
      maintainers = with stdenv.lib.maintainers; [ iyzsong ];
    };
  
  
negative.code:   ];
  
    buildInputs = [
      orc libXv pango libtheora cdparanoia
    ]
    ++ libintlOrEmpty
    ++ stdenv.lib.optional stdenv.isLinux alsaLib
    ++ stdenv.lib.optional (!stdenv.isDarwin) libvisual;
  
    propagatedBuildInputs = [ gstreamer ];
  
    configureFlags = if stdenv.isDarwin then [ 
      # Does not currently build on Darwin
      "--disable-libvisual"
      # Undefined symbols _cdda_identify and _cdda_identify_scsi in cdparanoia
      "--disable-cdparanoia"
    ] else null;
  
    NIX_LDFLAGS = if stdenv.isDarwin then "-lintl" else null;
  
    enableParallelBuilding = true;
  }
  