Qualification: I was introduced to FP a number of years ago and have finally reached a point where I feel that I have a deep understanding of FP in general. In my mind, Haskell is the "best" language out there ("best" in that it provides the best overall gain when all tradeoffs are considered).
I'm no longer confident that Haskell is the "best" language anymore. I was recently introduced to a language that might be even better than Haskell: Dyalog APL. (https://www.dyalog.com/). Try it out yourself (https://tryapl.org/)
To explain why, I recommend watching Aaron Hsu's videos on Dyalog APL:
- Does APL need a Type System? (https://www.youtube.com/watch?v=z8MVKianh54) - This is actually a very interesting question that is more nuanced than upon first glance.
- Design Patterns and Anti-Patterns in APL (https://www.youtube.com/watch?v=v7Mt0GYHU9A) - The main takeaway from this video for me was the principle of "Idioms over libraries."
- Higher Performance Tree-Wrangling, the APL way (https://www.youtube.com/watch?v=hzPd3umu78g) - Or how to model Trees without using pointers by using "Inverted Tables." (An inverted table is a table where the columns are the rows and the rows are the columns)