#[allow(unreachable_code)]
fn demo_drop(acquire_resource: bool) -> std::io::Result<()> {
    struct ResourceHolder {
        resource: Resource,
    }

    impl Drop for ResourceHolder {
        fn drop(&mut self) {
            self.resource.release()
        }
    }

    let resource = match acquire_resource {
        true => Some(Resource::new()),
        false => None,
    };
    let _holder = resource.map(|r| ResourceHolder { resource: r });

    println!("Resource used");
    return Err(std::io::Error::new(
        std::io::ErrorKind::Other,
        "Resource does not leak!",
    ));

    Ok(())
}