| // 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 Trait1<X> { |
| type Output; |
| } |
| |
| pub trait Trait2<X> {} |
| |
| pub struct A; |
| |
| impl<X, T> Trait1<X> for T where T: Trait2<X> { |
| type Output = (); |
| } |
| |
| impl<X> Trait1<Box<X>> for A { |
| //~^ ERROR conflicting implementations of trait |
| //~| hard error |
| //~| downstream crates may implement trait `Trait2<std::boxed::Box<_>>` for type `A` |
| type Output = i32; |
| } |
| |
| fn main() {} |
