27 lines
689 B
Rust
27 lines
689 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 Foo {
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type Out;
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}
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impl Foo for () {
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type Out = bool;
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}
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fn main() {
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type Bool = <() as Foo>::Out;
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let x: Bool = true;
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assert!(x);
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let y: Option<Bool> = None;
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assert_eq!(y, None);
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}
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