#![allow(dead_code, deprecated, unused_variables, unused_mut)]
use std::any::{Any, TypeId};
fn is_string(s: &dyn Any) -> bool {
    TypeId::of::<String>() == s.type_id()
}
fn main() {
    assert_eq!(is_string(& 0), false);
    assert_eq!(is_string(& "cookie monster".to_string()), true);
}