3 pub trait Plugin<E: ?Sized> {
8 fn get_ref<P: Plugin<Self>>(&mut self) -> Option<P::Error> {
14 impl Plugin<Foo> for Params {
18 impl<T: Copy> Pluggable for T {}
20 fn handle(req: &mut i32) {
21 req.get_ref::<Params>();
22 //~^ ERROR the trait bound `Params: Plugin<i32>` is not satisfied