#![warn(clippy::flat_map_option)] #![allow(clippy::redundant_closure, clippy::unnecessary_filter_map)] fn main() { // yay let c = |x| Some(x); let _ = [1].iter().flat_map(c); let _ = [1].iter().flat_map(Some); // nay let _ = [1].iter().flat_map(|_| &Some(1)); }