diff --git a/src/evaluator.js b/src/evaluator.js
index 128b82381..55af857e5 100644
--- a/src/evaluator.js
+++ b/src/evaluator.js
@@ -444,6 +444,7 @@ var PartialEvaluator = (function PartialEvaluatorClosure() {
                     case 'SA':
                     case 'AIS':
                     case 'TK':
+                      // TODO implement these operators.
                       info('graphic state operator ' + key);
                       break;
                     default: