processChild( callNode, arg, tree, columnExprList );
processChild( arg, tree, columnExprList );
	private void extractArguments( Node callNode, ScriptOrFnNode tree,			List columnExprList ) throws BirtException	{		Node arg = callNode.getFirstChild( ).getNext( );		while ( arg != null )		{			// need to hold on to the next argument because the tree extraction			// will cause us to lose the reference otherwise			Node nextArg = arg.getNext( );			processChild( callNode, arg, tree, columnExprList );			arg = nextArg;		}	}