diff --git a/src/static/js/Changeset.js b/src/static/js/Changeset.js
index fd658f869..a7ae8e713 100644
--- a/src/static/js/Changeset.js
+++ b/src/static/js/Changeset.js
@@ -507,6 +507,7 @@ exports.opAssembler = function () {
  */ 
 exports.stringIterator = function (str) {
   var curIndex = 0;
+  // newLines is the number of \n between curIndex and str.length
   var newLines = str.split("\n").length - 1
   function getnewLines(){
     return newLines