30 lines
840 B
Rust
30 lines
840 B
Rust
// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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pub trait Trait1<X> {
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type Output;
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}
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pub trait Trait2<X> {}
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pub struct A;
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impl<X, T> Trait1<X> for T where T: Trait2<X> {
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type Output = ();
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}
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impl<X> Trait1<Box<X>> for A {
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//~^ ERROR conflicting implementations of trait
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//~| hard error
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//~| downstream crates may implement trait `Trait2<std::boxed::Box<_>>` for type `A`
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type Output = i32;
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}
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fn main() {}
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