<p>I keep hearing that Flex is open source and I figured that a great way to learn about the inner workings would be to look at it. I can easily find the Flex SDK (<a href="http://opensource.adobe.com/wiki/display/flexsdk/Get+Source+Code" rel="noreferrer">http://opensource.adobe.com/wiki/display/flexsdk/Get+Source+Code</a>), but I'm wanting to look at the class definitions for the MXML core library (like NumericStepper). Have I misunderstood, or is this kind of thing available somewhere?</p>

<p>Note, I'm looking for the source of some core MXML components so I can see how they work internally, not for the compiler's source. Does what I've linked above have what I'm looking for and I just can't find it in the director structure?</p>

The open source stuff appears to be at:
```
```
http://opensource.adobe.com/wiki/display/flexsdk/Downloads
```
```
I don't know if everything is available there yet, there may be issues with third-party stuff.