What's the proper way to program in AS3?
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I've read a lot of books and watched videos on AS3 and they all teach very interesting techniques that I can harness and use. However, I'm in slight confusion because I've seen different techniques that contradict each other from different sources. For example, I've seen some developers write all their code within the timeline and handle it that way. Other times, I've seen developers handle their code in an .as file in Flex/Flash Builder/FlashDevelop. I know that there is no "right or wrong" way to do it, but what is the more preferred way by professionals?

As of now, I just use my .FLA to hold my assets and I write all my code in .AS.