#![allow(dead_code, deprecated, unused_variables, unused_mut)]
#![feature(slice_range)]
use std::slice;
fn main() {
    assert_eq!(None, slice::try_range(2..1, ..3));
    assert_eq!(None, slice::try_range(1..4, ..3));
    assert_eq!(None, slice::try_range(1..= usize::MAX, ..3));
}