What are the best languages for learning functional programming?

pragmatic functional programming.

6 months, after two years of F# with limited progress in learning functional programming, elm taught me in two months. Elm is simple on purpose, and pure.

much better than trying to make javascript do functional code

It looks so much like Elm and it works everywhere. With great community and very friendly Editor! If you like Elm then you ought to look at F# :-) They are so good at explaining new ideas. You will always be on the frontline of adopting new technologies!! Which is a big + to me!!