// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

fn hrtb(f: impl Fn(&u32) -> u32) -> u32 {
    f(&22) + f(&44)
}

fn main() {
    let sum = hrtb(|x| x * 2);
    assert_eq!(sum, 22*2 + 44*2);
}