> Because mutation gives you tremendous flexibility,
Interesting how perspective works. I frequently think of mutation as a really annoying restriction. In the presence of mutation, I can no longer assume things are what they say they are -- for they mave have changed between when I looked at them and when I speak of them.
That is fine, if you have a way of separating state from identity, and a way of synchronising the two when it makes sense to do so. Unfortunately, languages with uncontrolled mutation lack both.
Interesting how perspective works. I frequently think of mutation as a really annoying restriction. In the presence of mutation, I can no longer assume things are what they say they are -- for they mave have changed between when I looked at them and when I speak of them.
That is fine, if you have a way of separating state from identity, and a way of synchronising the two when it makes sense to do so. Unfortunately, languages with uncontrolled mutation lack both.