Subj : E4X: calling appendChild method with existing child as the argument
To   : netscape.public.mozilla.jseng
From : Martin Honnen
Date : Fri Apr 08 2005 04:07 pm


In E4X XML objects have a method called appendChild which behaves 
differently in regardance to object identity when the method is called 
with an existing child as the argument:

Spidermonkey:

js> var gods = <gods><god>Kibo</god><god>Xibo</god></gods>;
js> gods
<gods>
   <god>Kibo</god>
   <god>Xibo</god>
</gods>
js> gods.appendChild(gods.god[0])
<gods>
   <god>Kibo</god>
   <god>Xibo</god>
   <god>Kibo</god>
</gods>
js> gods.god[0] === gods.god[2]
true

so here after the appendChild the XML objects has two identical child 
elements at different positions.

Compare to Rhino 1.6 release 1 2004 11 30
js> var gods = <gods><god>Kibo</god><god>Xibo</god></gods>;
js> gods
<gods>
   <god>Kibo</god>
   <god>Xibo</god>
</gods>
js> gods.appendChild(gods.god[0])
<gods>
   <god>Kibo</god>
   <god>Xibo</god>
   <god>Kibo</god>
</gods>
js> gods.god[0] === gods.god[2]
false

Which behaviour is right, Spidermonkey's or Rhino's?

-- 

	Martin Honnen
	http://JavaScript.FAQTs.com/

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