diff --git a/lib/visitor/evaluator.js b/lib/visitor/evaluator.js
index <HASH>..<HASH> 100644
--- a/lib/visitor/evaluator.js
+++ b/lib/visitor/evaluator.js
@@ -202,21 +202,6 @@ Evaluator.prototype.visitPage = function(page){
 };
 
 /**
- * Visit noops.
- */
-
-Evaluator.prototype.visitString = 
-Evaluator.prototype.visitUnit =
-Evaluator.prototype.visitRGBA =
-Evaluator.prototype.visitHSLA =
-Evaluator.prototype.visitNull =
-Evaluator.prototype.visitComment =
-Evaluator.prototype.visitBoolean =
-Evaluator.prototype.visitLiteral = function(string){
-  return string;
-};
-
-/**
  * Visit Keyframes.
  */
 
diff --git a/lib/visitor/index.js b/lib/visitor/index.js
index <HASH>..<HASH> 100644
--- a/lib/visitor/index.js
+++ b/lib/visitor/index.js
@@ -25,7 +25,7 @@ var Visitor = module.exports = function Visitor(root) {
 
 Visitor.prototype.visit = function(node, fn){
   var method = 'visit' + node.constructor.name;
-  if (!this[method]) throw new Error('un-implemented ' + method);
-  return this[method](node);
+  if (this[method]) return this[method](node);
+  return node;
 };
revert noop visitor methods