Should I Learn Haskell or Scala?

Haskell is concise, safe and faster to use, whereas Scala is also concise, fast and safer with many libraries support. Haskell has first-class functions and pure, whereas Scala is strict and impure to use in terms of functional programming features.

Should I learn Haskell before Scala?

You don't have to learn Haskell to become a good Scala developers, but I think once you get to a certain level in Scala that having a deeper understanding of functional programming concepts really helps.

Is Haskell Worth Learning 2020?

Of course those languages have interesting qualities as well and it's worth learning them. But if you want to learn a language that will teach you the most and will push you to be a better programmer, then Haskell should be definitely your primary choice.