anchor.diff:  let
   
     buildIdea =
  -  { name, version, build, src, description, license }:
  +  { name, version, build, src, description, longDescription, license }:
   
     stdenv.mkDerivation rec {
       inherit name build src;
  
positive.code: 
  in {
  
    idea_community = buildIdea rec {
      name = "idea-community-${version}";
      version = "13.1.3";
      build = "IC-135.909";
      description = "IntelliJ IDEA 13 Community Edition";
      license = stdenv.lib.licenses.asl20;
      src = fetchurl {
        url = "http://download-ln.jetbrains.com/idea/ideaIC-${version}.tar.gz";
        sha256 = "62ed937ef68df16eef4d32772b6510835527f95020db1c76643f17ed2c067b51";
      };
    };
  
    idea_ultimate = buildIdea rec {
      name = "idea-ultimate-${version}";
      version = "13.1.3";
      build = "IU-135.909";
      description = "IntelliJ IDEA 13 Ultimate Edition";
      license = stdenv.lib.licenses.unfree;
      src = fetchurl {
        url = "http://download-ln.jetbrains.com/idea/ideaIU-${version}.tar.gz";
        sha256 = "6d99e49a63a197e19381a85535ab424a7832653db8cceb3bca7d53615ec7a53d";
      };
    };
  
  
negative.code:     meta = {
        homepage = http://www.jetbrains.com/idea/;
        inherit description;
        inherit longDescription;
        inherit license;
        maintainers = [ stdenv.lib.maintainers.edwtjo ];
        platforms = stdenv.lib.platforms.linux;
  