How add css class with Mootools

<div class="generic_layout_container layout_ride_ridespec">
</div>

How to programmicaly add an extra class or one more property with existing class to above div. I would like out put as follows

<div class="generic_layout_container layou开发者_运维百科t_ride_ridespec example_class">
</div>

Please excuse id/name solution, there is little difficulty to add an id or name for above element. Thanks

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MooTools does have an addClass() method. Eg:

HTML

<div id="myElement" class="testClass"></div>

Javascript

$('myElement').addClass('newClass');