Function get 

pub fn get<E>() -> Result<impl Deref<Target = E> + Debug + 'static, GetFailed>
where
    E: Any + Debug + 'static,

Returns a reference to a value in the current environment if it is present.

Errors

Returns an error if the requested type is not available in the local environment.

Examples

let msg = "hello!";
illicit::Layer::new().offer(String::from(msg)).enter(|| {
    assert_eq!(&*illicit::get::<String>().unwrap(), msg);
});

Returns GetFailed if the requested type is not in the environment:

assert!(illicit::get::<String>().is_err());