diff --git a/lib/carto/tree/definition.js b/lib/carto/tree/definition.js
index b4f14cc..2507c13 100644
--- a/lib/carto/tree/definition.js
+++ b/lib/carto/tree/definition.js
@@ -1,5 +1,7 @@
 (function(tree) {
-var assert = require('assert');
+var assert = require('assert') || {
+    ok: function() { }
+};
 
 tree.Definition = function Definition(selector, rules) {
     this.elements = selector.elements;
diff --git a/test/index.html b/test/index.html
index eab51af..6007b6d 100644
--- a/test/index.html
+++ b/test/index.html
@@ -17,11 +17,13 @@
         };
         (new carto.Parser(parse_env)).parse(style,
         function(err, ruleset) {
-          for (var i in ruleset.rules) {
-            for (var j in ruleset.rules[i].rules) {
-              document.getElementById('output').innerHTML += ruleset.rules[i].rules[j].eval(parse_env).toXML(parse_env) + ' ';
-            }
-          }
+          var definition = ruleset.toList(parse_env);
+          console.log(definition);
+          // for (var i in ruleset.rules) {
+          //   for (var j in ruleset.rules[i].rules) {
+          //     document.getElementById('output').innerHTML += ruleset.rules[i].rules[j].eval(parse_env).toXML(parse_env) + ' ';
+          //   }
+          // }
         });
       });
     }