#![warn(clippy::suspicious_map)] fn main() { let _ = (0..3).map(|x| x + 2).count(); let f = |x| x + 1; let _ = (0..3).map(f).count(); } fn negative() { // closure with side effects let mut sum = 0; let _ = (0..3).map(|x| sum += x).count(); // closure variable with side effects let ext_closure = |x| sum += x; let _ = (0..3).map(ext_closure).count(); // closure that returns unit let _ = (0..3) .map(|x| { // do nothing }) .count(); // external function let _ = (0..3).map(do_something).count(); } fn do_something(t: T) -> String { unimplemented!() }