[justinhj]

I don't think it's the simplest language out there but its parametric polymorphism is quite straightforward

[mcguire]

Once you figure out co- and contravariance, yes. But neurosurgery is straightforward, too. It's just getting from here to there.

[justinhj]

99% of the time Scala programmers don't have to worry about variance. I've been using Scala for over 5 years and it's never been more than a cursory concern, the defaults usually work fine. You just have the flexibility to work with it how you want if you need to. To compare it to neurosurgery is simply disingenuous

[mping]

I think you are generalising. But variance is specifically important for library developers where you have different uses for your code