Javascript String reversed()

//Just like you can add methods to your own constructor, you can also add methods and properties to 
//built in classes in JavaScript like Arrays and Objects.

//Add a reverse method to the String 'class' so that every instance of String can call reverse and reverse 
//itself.//w w  w  .ja  v a2  s .c om
  
String.prototype.reversed = function () {
 return this.split("").reverse().join("");
};

var iAmStr = "I am a string";

alert(String(iAmStr).reversed());