$.Callbacks: how to get length of the callback list
<p>I have the following code:</p>

<pre><code>var callbacks = $.Callbacks();
callbacks.add(fn1);
callbacks.add(fn2);
</code></pre>

<p>Is there any way to get the length of callbacks list. In my case it should be 2.
I've read <a href="https://api.jquery.com/jQuery.Callbacks/" rel="nofollow">the documentation</a>, but have not got the solution.</p>