#![allow(dead_code, deprecated, unused_variables, unused_mut)]
use std::io::{Error, ErrorKind};
fn main() {
    let x: Result<u32, Error> = Err(Error::new(ErrorKind::NotFound, "!"));
    assert_eq!(x.is_err_and(| x | x.kind() == ErrorKind::NotFound), true);
    let x: Result<u32, Error> = Err(Error::new(ErrorKind::PermissionDenied, "!"));
    assert_eq!(x.is_err_and(| x | x.kind() == ErrorKind::NotFound), false);
    let x: Result<u32, Error> = Ok(123);
    assert_eq!(x.is_err_and(| x | x.kind() == ErrorKind::NotFound), false);
    let x: Result<u32, String> = Err("ownership".to_string());
    assert_eq!(x.as_ref().is_err_and(| x | x.len() > 1), true);
    println!("still alive {:?}", x);
}