diff --git a/lib/date_format.js b/lib/date_format.js
index 32fa13c..a41ec4c 100644
--- a/lib/date_format.js
+++ b/lib/date_format.js
@@ -1,60 +1,65 @@
+"use strict";
 exports.ISO8601_FORMAT = "yyyy-MM-dd hh:mm:ss.SSS";
 exports.ISO8601_WITH_TZ_OFFSET_FORMAT = "yyyy-MM-ddThh:mm:ssO";
 exports.DATETIME_FORMAT = "dd MM yyyy hh:mm:ss.SSS";
 exports.ABSOLUTETIME_FORMAT = "hh:mm:ss.SSS";
 
 exports.asString = function(/*format,*/ date) {
-    var format = exports.ISO8601_FORMAT;
-    if (typeof(date) === "string") {
-        format = arguments[0];
-        date = arguments[1];
-    }
+  var format = exports.ISO8601_FORMAT;
+  if (typeof(date) === "string") {
+    format = arguments[0];
+    date = arguments[1];
+  }
 
-    var vDay = addZero(date.getDate());
-    var vMonth = addZero(date.getMonth()+1);
-    var vYearLong = addZero(date.getFullYear());
-    var vYearShort = addZero(date.getFullYear().toString().substring(3,4));
-    var vYear = (format.indexOf("yyyy") > -1 ? vYearLong : vYearShort);
-    var vHour  = addZero(date.getHours());
-    var vMinute = addZero(date.getMinutes());
-    var vSecond = addZero(date.getSeconds());
-    var vMillisecond = padWithZeros(date.getMilliseconds(), 3);
-    var vTimeZone = offset(date);
-    var formatted = format
-                      .replace(/dd/g, vDay)
-                      .replace(/MM/g, vMonth)
-                      .replace(/y{1,4}/g, vYear)
-                      .replace(/hh/g, vHour)
-                      .replace(/mm/g, vMinute)
-                      .replace(/ss/g, vSecond)
-                      .replace(/SSS/g, vMillisecond)
-                      .replace(/O/g, vTimeZone);
-    return formatted;
+  var vDay = addZero(date.getDate());
+  var vMonth = addZero(date.getMonth()+1);
+  var vYearLong = addZero(date.getFullYear());
+  var vYearShort = addZero(date.getFullYear().toString().substring(3,4));
+  var vYear = (format.indexOf("yyyy") > -1 ? vYearLong : vYearShort);
+  var vHour  = addZero(date.getHours());
+  var vMinute = addZero(date.getMinutes());
+  var vSecond = addZero(date.getSeconds());
+  var vMillisecond = padWithZeros(date.getMilliseconds(), 3);
+  var vTimeZone = offset(date);
+  var formatted = format
+    .replace(/dd/g, vDay)
+    .replace(/MM/g, vMonth)
+    .replace(/y{1,4}/g, vYear)
+    .replace(/hh/g, vHour)
+    .replace(/mm/g, vMinute)
+    .replace(/ss/g, vSecond)
+    .replace(/SSS/g, vMillisecond)
+    .replace(/O/g, vTimeZone);
+  return formatted;
 
-    function padWithZeros(vNumber, width) {
-	var numAsString = vNumber + "";
-	while (numAsString.length < width) {
-	    numAsString = "0" + numAsString;
-	}
-	return numAsString;
+  function padWithZeros(vNumber, width) {
+    var numAsString = vNumber + "";
+    while (numAsString.length < width) {
+      numAsString = "0" + numAsString;
     }
+    return numAsString;
+  }
+  
+  function addZero(vNumber) {
+    return padWithZeros(vNumber, 2);
+  }
 
-    function addZero(vNumber) {
-	return padWithZeros(vNumber, 2);
+  /**
+   * Formats the TimeOffest
+   * Thanks to http://www.svendtofte.com/code/date_format/
+   * @private
+   */
+  function offset(date) {
+    // Difference to Greenwich time (GMT) in hours
+    var os = Math.abs(date.getTimezoneOffset());
+    var h = String(Math.floor(os/60));
+    var m = String(os%60);
+    if (h.length == 1) {
+      h = "0" + h;
     }
-
-    /**
-     * Formats the TimeOffest
-     * Thanks to http://www.svendtofte.com/code/date_format/
-     * @private
-     */
-    function offset(date) {
-	// Difference to Greenwich time (GMT) in hours
-	var os = Math.abs(date.getTimezoneOffset());
-	var h = String(Math.floor(os/60));
-	var m = String(os%60);
-	h.length == 1? h = "0"+h:1;
-	m.length == 1? m = "0"+m:1;
-	return date.getTimezoneOffset() < 0 ? "+"+h+m : "-"+h+m;
+    if (m.length == 1) {
+      m = "0" + m;
     }
+    return date.getTimezoneOffset() < 0 ? "+"+h+m : "-"+h+m;
+  }
 };