error: the loop variable `i` is only used to index `ns`.
  --> $DIR/needless_range_loop.rs:8:5
   |
8  | /     for i in 3..10 {
9  | |         println!("{}", ns[i]);
10 | |     }
   | |_____^
   |
   = note: `-D needless-range-loop` implied by `-D warnings`
help: consider using an iterator
   |
8  |     for <item> in ns.iter().take(10).skip(3) {
   |         ^^^^^^