You can’t reference an object during initialization when using object literal syntax. You need to reference the object after it is created.
settings.birthplace = settings.country;
Only way to reference an object during initialization is when you use a constructor function.
This example uses an anonymous function as a constructor. The new object is reference with this
.
var settings = new function() {
this.user = "someuser";
this.password = "password";
this.country = "Country";
this.birthplace = this.country;
};