javascript infinite loop with defineSetter

Question

I have the following the code -

var obj = {
    name : "Yosy"
};

obj.__defineSetter__("name",function(v){
    alert(v);
});

The problem is -
If I change obj.name to something else and console.log(obj) I will get undefined on the name property. So I tried to fix obj.defineSetter to this -

var obj = {
    name : "Yosy"
};

obj.__defineSetter__("name",function(v){
    alert(v);
    this.name = v;
});

If you the change name to "ABC" or something else you will get an infinite loop because in the defineSetter I am setting the value of the property "name".
what to do?

Answer 1

Well, if you want to be able to use the name property like normal and still alert the value as well, you should name your object field differently, like this:

var obj = {
    _name : "Yosy"
};

obj.__defineSetter__("name",function(v){
    alert(v);
    this._name = v;
});

obj.__defineGetter__("name",function() {
    return this._name;
});

or something like this:

var obj = {
    fields: {
        name : "Yosy"
    }
};

obj.__defineSetter__("name",function(v){
    alert(v);
    this.fields.name = v;
});

obj.__defineGetter__("name",function() {
    return this.fields.name;
});

to prevent the setter from firing again when you set the property.

EDIT:

For anyone interested, here's some documentation: https://developer.mozilla.org/en/Core_JavaScript_1.5_Guide/Working_with_Objects#Defining_Getters_and_Setters