Actionscript - Variable Assignment without reference?

Should be easy. I have an object. I want to modify it, but before i do I want to save a copy of it that I can go back to. I tried setting copy = original but when i modify the attributes of the original the copy also shows the changes. I am assuming this is because in actionscript any time you assign, it really just stores a reference to the original object. So whats the best way for me to store a copy of the original object for later use?

From stackoverflow

•  // duplicate any given Object (not MCs)  
   Object.prototype.copy = function()  
   {  
       ASSetPropFlags(Object.prototype,["copy"],1);  
  
       var _t = new this.__proto__.constructor(this) //
  
       for(var i in this){  
           _t[i] = this[i].copy()  
       }  
       return _t  
   };
  

  Usage

  x = ["1","2","3",[4,5],[{a:1,b:2}]]
  
  y = x.copy()
  
  y[0] = 0
  
  y[3][0]="d"
  
  trace(x)
  
  trace(y)
  

  Lillemanden : This is a terrible solution, any object just bit complex would not be copied properly. Furthermore adding to the Object prototype is not good practice. I would even go as far as to say adding anything to the protype is bad practice. It's more a left over relic than a feature.

• What you are looking for is a deep copy of the object rather then passing by reference. I found the answer here which uses the new ByteArray class in AS3:

  http://www.kirupa.com/forum/showthread.php?p=1897368

  function clone(source:Object):* {
   var copier:ByteArray = new ByteArray();
   copier.writeObject(source);
   copier.position = 0;
   return(copier.readObject());
  

  }

  Which you then use like this:

  newObjectCopy = clone(originalObject);
  

  Cheers!

• var newObj:Object = Object(ObjectUtil.copy(oldObj));
  

  "Copies the specified Object and returns a reference to the copy. The copy is made using a native serialization technique. This means that custom serialization will be respected during the copy.

  This method is designed for copying data objects, such as elements of a collection. It is not intended for copying a UIComponent object, such as a TextInput control. If you want to create copies of specific UIComponent objects, you can create a subclass of the component and implement a clone() method, or other method to perform the copy."

  http://livedocs.adobe.com/flex/3/langref/mx/utils/ObjectUtil.html#copy()