Just to note he's not actually right on javascript dealing with string literals inside closures in the same way (js will reuse the same memory for all instances

Just to note he's not actually right on javascript dealing with string literals inside closures in the same way (js will reuse the same memory for all instances of "Foobar" in his map example). I'm pretty sure he just means the general concept of allocations per closure instance will be familiar though, which is correct.