anchor.diff:      xelb = callPackage ({ cl-generic, elpaBuild, emacs, fetchurl, lib }:
       elpaBuild {
           pname = "xelb";
  -        version = "0.5";
  -        src = fetchurl {
  -          url = "http://elpa.gnu.org/packages/xelb-0.5.tar";
  -          sha256 = "1wypffg492r2a3h136c6mphsbgimxcipsarm971z56kpy3lwi4sb";
  +        version = "0.6";
  +        src = fetchurl {
  +          url = "http://elpa.gnu.org/packages/xelb-0.6.tar";
  +          sha256 = "1m91af5srxq8zs9w4gb44kl4bgka8fq7k33h7f2yn213h23kvvvh";
           };
           packageRequires = [ cl-generic emacs ];
           meta = {
  
positive.code:     test-simple = callPackage ({ cl-lib ? null, elpaBuild, fetchurl, lib }:
      elpaBuild {
          pname = "test-simple";
          version = "1.1";
          src = fetchurl {
            url = "http://elpa.gnu.org/packages/test-simple-1.1.el";
            sha256 = "0s8r6kr0a6n1c20fraif2ngis436a7d3gsj351s6icx6bbcjdalw";
          };
          packageRequires = [ cl-lib ];
          meta = {
  
negative.code:       }) {};
      math-symbol-lists = callPackage ({ elpaBuild, fetchurl, lib }: elpaBuild {
          pname = "math-symbol-lists";
          version = "1.1";
          src = fetchurl {
            url = "http://elpa.gnu.org/packages/math-symbol-lists-1.1.tar";
            sha256 = "06klvnqipz0n9slw72fxmhrydrw6bi9fs9vnn8hrja8gsqf8inlz";
          };
          packageRequires = [];
          meta = {
  