I’m trying to write a code which borrow a mutable copy of the last member of a vector and then change another member of the vector. There is a check that the vector has more than 2 elements so there is no changes to the same element.

pub fn adjust(&mut self) {
    if self.vec.len() < 2 {
        return;
    }
    let vec_last = self.vec.last_mut().unwrap();
    let mut iter = vec_last.iter_mut();
    while let Some(i) = iter.next() {
        self.vec[0].push(i.clone());
    }
}

The compiler produces the error cannot borrow self.vec as mutable more than once at a time which is expected.

Is there a way to do such changes without triggering the error?

Cheers