 <p>Parameteric types ( the word 'generics' is usually used in ECMAScript for <a href="https://developer.mozilla.org/en/New_in_JavaScript_1.6#Array_and_String_generics" rel="nofollow noreferrer">generic methods</a>, rather than the combination of parametric types and runtime polymorphism used in Java ) were <a href="http://wiki.ecmascript.org/doku.php?id=proposals:type_parameters" rel="nofollow noreferrer">proposed</a> as part of ES4, but ES4 fractured and much of the type system proposed for ES ( including the parts implemented in ActionScript ) are not going into the next version. I can't say whether or not Adobe would want to go that way by themselves.</p>