I used to recommend that to learn functional programming, one should learn Haskell. Nowadays, I think that advice isn’t as optimal. The reason Haskell is hard is because of the massive type system, not because it is functional. A better avenue for functional programming would be a lisp-derivative like Racket or Clojure. That way you focus on recursion and functional design patterns rather than the type system. (I still think everyone should learn Haskell at some point both for the type system and for the functional programming aspect). Given that AI will be writing most of the code in the future, it seems to me that the skill of a programmer is to rigorously specify what behavior is expected, and then let the AI take care of it. Haskell is one of the top languages for rigorous specifications. Also some fun lore about me: I used Clojure in production at one point simply because I could and I was bored of the common languages. I was basically unfireable so my boss had to go along with it even though he was (rightly) skeptical about using a language that is impossible to hire for. Yes, I was that programmer before.