Possible Duplicate:

Access the first property of an object

I have a javascript object like this:

var list = {

    item1: a,

    item2: b,

    item3: c,

    item4: d

};

Using reflection in JS, I can say list[item1] to get or set each member programmatically, but I don't want to rely on the name of the member (object may be extended). So I want to get the first member of this object.

If I write the following code it returns undefined. Anybody knows how this can be done?

var first = list[0]; // this returns undefined