Add handler multiple times in jquery

How does jquery handle event assign开发者_如何学编程ment when it comes to assigning the same handler multiple times? Let's say I have

<div class="draggable">Some Text</div>

Are there any side effects (performance or otherwise) from calling the following multiple times?

$('.draggable').draggable();

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If you bind a event like 'keydown' multiple times to an element, it will get attached to a queue of event handlers. So you can do the math, the more handlers are called, the slower it will perform.