> functional use requires cloning If you're suggesting that functional updates require the entire collection to be copied, that's not correct. Only a small am

> functional use requires cloning If you're suggesting that functional updates require the entire collection to be copied, that's not correct. Only a small amount of data (oproportional to the logarithm of the size of the collection) has to be copied on each update. The result is that functional collections are quite practical for most uses. They have stylistic benefits as well.