does Backbone.Models this.get() copy an entire array or point to the same array in memory

 Person = Backbone.Model.extend({
        defaults: {
            name: 'Fetus',
            age: 0,
            children: []
        },
        initialize: function(){
            alert("Welcome to this world");
        },
        adopt: function( newChildsName ){
            var children_array = this.get("children");
            children_array.push( newChildsName );
            this.set({ children: children_array });
        }
    });

    var person = new Person({ name: "Thomas", age: 67, children: ['Ryan']});
    person.adopt('John Resig');
    var children = person.get("children"); // ['Ryan', 'John Resig']

In this example code we have:

children_array = this.get("children")

I was thinking this would just point to the same array in memory (and so would be O(1)). However then I thought that would be a design floor because one could manipulate the array without using this.set() and then event listeners wouldn't fire.

So I'm guessing it (somehow magically) copies the array??

http://backbonejs.org/#Model-set

What happens?

edit: I just found the implementation in the backbone source code at https://github.com/documentcloud/backbone/blob/master/backbone.js (I've pasted relevant code at bottom)

Get returns:

return this.attributes[attr]

so this would just point to the same array in memory right? So one could change the array without using set() and that would be bad.. ? am i correct?

get: function(attr) {
      return this.attributes[attr];
    },

    // Get the HTML-escaped value of an attribute.
    escape: function(attr) {
      var html;
      if (html = this._escapedAttributes[attr]) return html;
      var val = this.get(attr);
      return this._escapedAttributes[attr] = _.escape(val == null ? '' : '' + va