fn pop(input: &mut &mut[u8]) {
    let old = std::mem::replace(input, &mut []);
    let (_, r) = old.split_at_mut(1);
    *input = r;
}



fn main () {


    let mut cursor = &mut ([0u8, 1u8, 2u8, 3u8, 4u8][..]);

    // Pop 1 element
    let (_, r) = cursor.split_at_mut(1);
    cursor = r;

    // Pop 1 element
    pop(&mut cursor);

    cursor[0] = 99;
    dbg!(cursor);


}