anchor.diff:  { stdenv, fetchurl, itstool, buildPythonPackage, python27, intltool, makeWrapper
   , libxml2, pygobject3, gobjectIntrospection, gtk3, gnome3, pycairo, cairo
  -, hicolor_icon_theme
   }:
   
   
   let
  -  minor = "3.12";
  -  version = "${minor}.3";
  +  minor = "3.14";
  +  version = "${minor}.0";
   in
   
   buildPythonPackage rec {
  
positive.code:   preFixup = ''
      wrapProgram $out/bin/meld \
        --prefix GI_TYPELIB_PATH : "$GI_TYPELIB_PATH" \
        --prefix XDG_DATA_DIRS : "$GSETTINGS_SCHEMAS_PATH:$out/share"
    '';
  
    patchPhase = ''
      sed -e 's,#!.*,#!${python27}/bin/python27,' -i bin/meld
    '';
  
    pythonPath = [ gtk3 ];
  
    meta = with stdenv.lib; {
      description = "Visual diff and merge tool";
      homepage = http://meld.sourceforge.net;
      license = stdenv.lib.licenses.gpl2;
      platforms = platforms.linux ++ stdenv.lib.platforms.darwin;
    };
  
negative.code: 
    src = fetchurl {
      url = "mirror://gnome/sources/meld/${minor}/meld-${version}.tar.xz";
      sha256 = "0g0h9wdr6nqdalqkz4r037569apw253cklwr17x0zjc7nwv2j3j3";
    };
  
    buildInputs = [
      python27 intltool makeWrapper itstool libxml2
      gnome3.gtksourceview gnome3.gsettings_desktop_schemas pycairo cairo
      gnome3.defaultIconTheme
    ];
    propagatedBuildInputs = [ gobjectIntrospection pygobject3 gtk3 ];
  
  