| // 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. |
| |
| struct Params; |
| |
| pub trait Plugin<E: ?Sized> { |
| type Error; |
| } |
| |
| pub trait Pluggable { |
| fn get_ref<P: Plugin<Self>>(&mut self) -> Option<P::Error> { |
| None |
| } |
| } |
| |
| struct Foo; |
| impl Plugin<Foo> for Params { |
| type Error = (); |
| } |
| |
| impl<T: Copy> Pluggable for T {} |
| |
| fn handle(req: &mut i32) { |
| req.get_ref::<Params>(); |
| //~^ ERROR the trait bound `Params: Plugin<i32>` is not satisfied |
| } |
| |
| fn main() {} |
