#![allow(dead_code, deprecated, unused_variables, unused_mut)]
fn main() {
    let a = ['a', 'b', 'c'];
    let mut iter = a.into_iter().enumerate();
    assert_eq!(iter.next(), Some((0, 'a')));
    assert_eq!(iter.next(), Some((1, 'b')));
    assert_eq!(iter.next(), Some((2, 'c')));
    assert_eq!(iter.next(), None);
}