Most file formats for programs are technically just 1's and 0's. However when those files are opened in a text editor they are illegible or completely "empty" when viewed as text.
The only big time file formats that I can think of that are relatively "editable" would be the Adobe Illustrator format or the EPS format. I've managed to fix a few AI files using a text editor. I don't recommend it... not fun.
The really cool programs

have "readable" text only file formats. The file format is logical and structured in a way to allow normal humans to make sense of it. This is wonderful. It allows for editing and fixing files or creating applications that can do all kinds of things to those files without a lot of magic coding mumbo jumbo.
I am not completely sure what format the AS file is but it looks similar to XML format. I am just guessing of course.
Another animation program file format that is text is the Animation Master file format. Totally completely regular old ascii text. Over the years I have been able to fix corrupted files by comparing a "broken" file to a "clean" normal file and fix the bits that got messed up.
You just can't do that with most program file formats.
I have a cheesy programming application. It isn't really powerful but it will build Mac and Windows applications. I have often thought it would be possible to create an application with this that could open AS files and do things like manage "instances" of other files stored as "layers"... sort of like a Flash type thing.
-vern