I mean, what would be best for my mind-shaping? What would be funniest? What would make best effect on my résumé?
In passed twelve months I learnt Clojure, automata theory (applied it through regex and grammars with instaparse) and logic programming (with core.logic)
Yeah I know that, maybe I could even use Swift to do ML. The thing is, like everybody I have limited time and learning ability so I'm thinking about what I should use my time for.
Actually I believe ML will shape my mind but maybe Swift could do this also. About money, not sure what a recruiter would value the most.
Machine learning. Very broad and educational. It'd take 15 minutes, then 3 weeks to learn Swift, and then all you'd have is another language you're familiar with. Actually scratch that. Go long on machine learning WHILE ALSO skimming through Swift docs such that you'll be familiar with both.