I've really liked that, too. Its approach to mutability is also very nice. The combined result may not be nearly as principled as the Haskell way of doing cont

I've really liked that, too. Its approach to mutability is also very nice. The combined result may not be nearly as principled as the Haskell way of doing controlled mutability with double-checking from the compiler that you aren't breaking your own rules, but it's a nice pragmatic compromise that's easy to understand without having to rewire the way you think about programming.