Why &mut is working in this case, when method takes ownership

help
1

Hi,
I'm struggling to understand why and how this code works:

fn iter1() {
    let samples = vec![1, 2, 3];
    let mut iter = samples.into_iter();
    for i in 0..3 {
        let n = (&mut iter).count();
        println!("Iterator has {} items", n)
    }
}

count method takes ownership of the iterator. So without &mut it'll give obvious "use of moved value" error. But with &mut it works. However if it would just dereference, it should give error "cannot move out of borrowed content"? What exactly is happening in background?

2

Emphasis on the "if". It doesn't give that error because it isn't just dereferencing.

If you look at the documentation for Iterator, you'll see there's an implementation for &mut I where I: Iterator.

3

Thanks. I see now, pretty cool.