One of the most powerful idioms available in JavaScript is the anonymous function closure: e.g. (function(){})();. If you are unfamiliar with this, it simply creates an anonymous scope bubble that can be used to prevent automatic global variables, or trick JavaScript into allowing private variables. Unfortunately, this idiom isnt available in ActionScript 2.0. It simply doesnt work. (As of ActionScript 3.0, it works perfectly.)

This means that, on the surface, the only way to prevent time line variables from being constantly created is an init function of sorts. (ActionScript 2.0 has a pseudo global object which is the main time line of a movie level, and a totally global object named _global.) This also means that private variables are restricted to the creation of object classes. I personally get annoyed at times with classes in ActionScript. One of the things that has always bugged me with ActionScript 2.0 and the introduction of classes is that they are hard to make portable. (I work on no less than 3 computers in a single week, and 4-5 when on business trips, so portability is paramount to my work.) Rather than being able to simply include the classes in the same folder as the flash working file (*.fla), you must specify where on the computer the includes are. This is just annoying if you work on the file on several different computers. There are a couple of ways to avoid naming the class include folder on each computer, but they are as much of a pain as the default method. Fortunately, there is a solution.

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