Just a little Actionscript tip. I’ve been updating a large Flash app created elsewhere and trying to optimize the code. In many places in the 2 dozen or so classes, there are checks for whether a variable is empty (”") or undefined. I had used this comparison myself many times, and find it annoying that Flash doesn’t have a one-size-fits-all way to check if data exists for a variable. PHP’s empty() method comes to mind. So I did an experiment and Flash does work like empty() without a special method. If you do this:

if ($myvar) { /* do stuff * }

then the if statement will return false if:

a) the variable is an empty string, ie. “”
b) the variable is undefined
c) the variable is set to null
d) the variable is zero, ie. 0

Of course you have to be careful if the variable is boolean, or what the type is, but if you know it’s supposed to be a string, then it’s easy.