Yes, but it doesn't bolster your argument as much as you think. The state monad in Haskell offers a more principled (some say annoying) way of dealing with muta

Yes, but it doesn't bolster your argument as much as you think. The state monad in Haskell offers a more principled (some say annoying) way of dealing with mutation. IORef's if I recall correctly offer the type of mutation similar to what is colloquially thought of as mutation. These add to your argument a bit, but they're usually seen more of a last resort