> Haskell is much cleaner than Scala. But I think most people will get stuck reasoning about laziness (which is necessary to avoid space leaks). Another problem is that many modules require extensive use of the type system and advanced concepts to use (monads, arrows, lenses, existential typing, etc.).
Not to mention that many modules require various GHC extensions.
I'm not so sure about Kotlin. From what I can see, it's pretty straightforward, with no risk or ambition of achieving the anxiety-inducing Scala method signatures. On the other hand, it seems to be seriously lacking in the marketing department, which can often be enough to push forward a language even when a better option is available.
Not to mention that many modules require various GHC extensions.
I'm not so sure about Kotlin. From what I can see, it's pretty straightforward, with no risk or ambition of achieving the anxiety-inducing Scala method signatures. On the other hand, it seems to be seriously lacking in the marketing department, which can often be enough to push forward a language even when a better option is available.