IntoIterator

Here’s an important takeaway from our VecIter in the previous lesson: a Vec on its own doesn’t have enough information to be iterated over. We need to know the current position in the iteration, and a Vec doesn’t have that information. Therefore, it’s impossible to have an Iterator implementation for Vec. And sure enough, there is no such implementation available. We can even demonstrate that by trying to use the next method directly on a Vec: