Peachpit, Written by Kris Hadlock
Parameters are an essential construct of a method, and the ability to type parameters is of the utmost importance. But what if you are not sure of the value type for a parameter?
In ActionScript 2, the way to avoid this data type dilemma is to type the parameter as an Object or leave it untyped, then Flash will type it as an Object by default.
ActionScript 3 offers a more elegant solution: the wildcard parameter.