Empty ranges result in no iterations, making any loop a no-op. Trying to index slices using reversed ranges will result in runtime panics. Both
scenarios lead to bugs or logical errors in the code.
Code examples
Noncompliant code example
fn main() {
(10..=0).for_each(|x| println!("{}", x)); // Noncompliant: Empty range
let arr = [1, 2, 3, 4, 5];
let sub = &arr[3..1]; // Noncompliant: Reversed slice indexing
}
Compliant solution
fn main() {
(0..=10).rev().for_each(|x| println!("{}", x)); // Compliant: Properly reversed range for iteration
let arr = [1, 2, 3, 4, 5];
let sub = &arr[1..3]; // Compliant: Valid slice indexing
}
