* Pattern matching with totality checking. Warn us if a cased is missed. * Higher-kinded types. Can a List<Int> and a Stream<Int> both be considered a T<Int>

* Pattern matching with totality checking. Warn us if a cased is missed. * Higher-kinded types. Can a List<Int> and a Stream<Int> both be considered a T<Int> ? * Differentiate between functions with and without effects.