If you want to learn a functional language absolutely do not learn Haskell. If you're interested in static functional programming, learn Elm and then F#/OCaml.

If you want to learn a functional language absolutely do not learn Haskell. If you're interested in static functional programming, learn Elm and then F#/OCaml. If you're interested in dynamically typed then learn Clojure or possibly Racket. That's it. Spending time learning Haskell as your first (or even second) fp language is a terrible idea and has done more to slow FP adoption than anything. You can learn Elm literally in a weekend it's so small and well organized (go to their site and follow the tutorial). The concepts you pick up will double the speed you learn any other static FP. F# on .net core is cross platform and can run via a vs code plugin. Plus you have a batteries included full class library of practical needs via dot net. Clojure is very productive, great concepts as well. A bit worse tooling / debuggingqgen you have to drop down to deal with java, but also had batteries included java libs. Racket is probably the most isolated of the above. A scheme dialect and a bit closer to historical scheme and Lisp. Don't learn Haskell it's a horrible use of time as a first language. You get 80% of the value in the above languages in somewhere between 1/10 to 1/4th the effort (depending on which lang you choose), and have learned a more practical language, and will actually learn that lang plus Haskell faster than if you had started in Haskell.