> and an even better one to read...and it's easy to understand which parts of the code do what

It's not always easy to understand (from Odersky himself https://gist.github.com/odersky/6b7c0eb4731058803dfd#file-fo...):

def toVector: Vector[B] = fold(Vector[B]())(_ :+ _)(_ ++ _)

To a Scala veteran, I'm sure that's easy to understand; to someone who's been learning the language (like me) it looks like gibberish.

I've also had to write code like this:

client.post(args).mapTo[Response].map(r => (r.success, r.serverException, r.unhandledException) match {

case (Some(response), None, None) => response

case (None, Some(serverEx), None) => throw serverEx

case (None, None, Some(unhandledEx)) => throw unhandledEx

})

simply because of the underlying api that other co-workers have built. When it takes you longer than 30 seconds to explain how a piece of code works to others, something is wrong.

All that being said, I do like the language; just not the compile times. It's also pretty close to ruby (with which I'm most familiar):

ruby:

numbers = [1, 2, 3, 4, 5]

numbers.select { |n| n >= 4 }

# [4, 5]

Scala:

val numbers = List(1, 2, 3, 4, 5)

numbers.filter(n => n >= 4)

// List(4, 5)