| // 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. |
| |
| pub trait Foo { |
| type Out; |
| } |
| |
| impl Foo for () { |
| type Out = bool; |
| } |
| |
| fn main() { |
| type Bool = <() as Foo>::Out; |
| |
| let x: Bool = true; |
| assert!(x); |
| |
| let y: Option<Bool> = None; |
| assert_eq!(y, None); |
| } |
