use std::any::Any;
use std::sync::Arc;

trait FooTrait: Any {
    fn method(&self) -> u32;
}

struct Foo {
    value: u32,
}

impl FooTrait for Foo {
    fn method(&self) -> u32 {
        self.value
    }
}

fn new_foo() -> Option<Arc<FooTrait + Send + Sync + 'static>> {
    Some(Arc::new(Foo { value: 99 }))
}

fn test(value: Arc<dyn Any + Send + Sync + 'static>) {
    if let Ok(s) = value.downcast::<Foo>() {
        println!("{}", s.method());
    }
}

type Object = Arc<dyn Any + Send + Sync + 'static>;

fn main() {
    let cast: Option<Object> = new_foo().map(|c| {
        c.downcast::<>()
    });

    test(cast);
    test(Arc::new(1));
}