23 lines
732 B
Rust
23 lines
732 B
Rust
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// Copyright 2016 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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// Coherence error results because we do not know whether `T: Foo<P>` or not
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// for the second impl.
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use std::marker::PhantomData;
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pub trait Foo<P> {}
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impl <P, T: Foo<P>> Foo<P> for Option<T> {} //~ ERROR E0119
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impl<T, U> Foo<T> for Option<U> { }
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fn main() {}
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