It seems effect types are things people want, but few languages have managed to reify them, make them something we can all use. (Like, in -- cough cough -- Java et. al.) Any thoughts on how/when it will get to be more mainstream? Good enough that you'd risk using in production (at least w/in a group that is a little on the cutting-edge)? What things should a decent effect system support? Not only null checks I hope. (I was wondering about, via 'pilud' list, is how to rigorously handle immutable/mutable conversion/interaction.) Or are we just stuck with monads and related transformer boilerplate (and confusion to people like me)?