anchor.diff:  
       # Now Let's build xdebug if flag has been given
       # TODO I think there are better paths than the given below
  -    if [ -n $flag_set_xdebug ]; then
  +    if [ -n "$flag_set_xdebug" ]; then
         PATH=$PATH:$out/bin
         tar xfz $xdebug_src;
         cd xdebug*
  
positive.code:       xdebug = {
          buildInputs = [ automake autoconf ];
          xdebug_src = args.fetchurl {
            name = "xdebug-2.0.2.tar.gz";
            url = "http://xdebug.org/link.php?url=xdebug202";
            sha256 = "1h0bxvf8krr203fmk1k7izrrr81gz537xmd3pqh4vslwdlbhrvic";
          };
        };
      };
  
negative.code:     soapSupport = getConfig ["php" "soap"] true;
      zlibSupport = getConfig ["php" "zlib"] true;
      opensslSupport = getConfig ["php" "openssl"] true;
      xdebugSupport = getConfig ["php" "xdebug"] false;
      mbstringSupport = getConfig ["php" "mbstring"] true;
      gdSupport = getConfig ["php" "gd"] true;
    };
  