error: avoid using `collect()` when not needed --> $DIR/ice-5872.rs:4:39 | LL | let _ = vec![1, 2, 3].into_iter().collect::>().is_empty(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: replace with: `next().is_none()` | = note: `-D clippy::needless-collect` implied by `-D warnings` error: aborting due to previous error