This is an attempt at an open source parser / compiler for swift written in ObjC. I did this for an organization headed by Aral Balkan a few years ago. It is not finished, but it does serve as an example of a compiler writen in ObjC and How to generate an AST. The Swift team changed their syntax 4 times in one year so I gave up trying to follow them. The code is here for posterity.
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