I imagine that some of it is also the almost entirely strictly functional design of the language. Some of the ways it makes you write things should make certain tasks like that easier for the compiler. It should be almost always known at compile time when it'll be able to reap things.
Right. For one thing, nothing in Erlang is mutable: To change something, you copy it and change the copy. This sounds like it should make generational garbage collection easier (to a first approximation, nothing in the older generation is being used) but I don't know.
