error: this loop could be written as a `for` loop
  --> $DIR/while_let_on_iterator.rs:8:5
   |
LL |     while let Option::Some(x) = iter.next() {
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `for x in iter`
   |
   = note: `-D clippy::while-let-on-iterator` implied by `-D warnings`

error: this loop could be written as a `for` loop
  --> $DIR/while_let_on_iterator.rs:13:5
   |
LL |     while let Some(x) = iter.next() {
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `for x in iter`

error: this loop could be written as a `for` loop
  --> $DIR/while_let_on_iterator.rs:18:5
   |
LL |     while let Some(_) = iter.next() {}
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `for _ in iter`

error: this loop could be written as a `for` loop
  --> $DIR/while_let_on_iterator.rs:97:9
   |
LL |         while let Some(_) = y.next() {
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `for _ in y`

error: aborting due to 4 previous errors