方括号前的符号

Question

I'm currently maintainging some DS/JS code in Demandware and I just found that :

var XmlReponse : XML = new XML(result.object.text);
status = XmlReponse.@["STATUS"];

What does this unusual "@[...]" syntax do ?

It could have something to do with ECMA-357 specification (aka "E4X"), but I'm not sure : in the DW docs (needs credentials), it is said :

"You can read values from an XML object the same way you would from standard ECMAScript objects"

var quantity = order.item(0).@quantity;
var singleItem = order.item.(@quantity == 1);

That seems to explain the @ but let me skeptical about the following square brackets, maybe some kind of dynamic property ?

Thanks :)

Answer 1

From reading the ex4 manual it seems to read a property of an xml element. I don't see that reading the indexer would be any different

Your mentioned code would then read the attribute STATUS on the xmlresponse

The code on the linked ex4 manual status:

E4X allows you to access the attributes of a particular element with the .@ operator. The most basic case would look something like.

var element = <foo bar="1"/>
element.@bar = 2;