Action in action set represents single instruction that will be invoked in future. Inline functions or lambda expressions are too noisy to write. As you have seen in previous section, inline function or function references are valid actions as well, following used inside an anonymous object lets you perform respective actions.
$x.data('property','value') //or $x.data({ property1: value1, property2: value2 })
$x.alert("message") // this will not display alert, but it is a callback to display an alert
$x.isValid(action) // this will only execute actions if current element is valid
$x.confirm('are you sure message?', actions...)
Confirm action requires an array, in which first item inside array is message for confirmation and next item is an action set, action sets can have nested action sets as well.