#![allow(dead_code, deprecated, unused_variables, unused_mut)]
fn main() {
    assert!([1, 2, 2, 9].iter().is_sorted_by(| a, b | a <= b));
    assert!(! [1, 2, 2, 9].iter().is_sorted_by(| a, b | a < b));
    assert!([0].iter().is_sorted_by(| a, b | true));
    assert!([0].iter().is_sorted_by(| a, b | false));
    assert!(std::iter::empty::< i32 > ().is_sorted_by(| a, b | false));
    assert!(std::iter::empty::< i32 > ().is_sorted_by(| a, b | true));
}