31 lines
847 B
Rust
31 lines
847 B
Rust
// Copyright 2015 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 MakeRef<'a> {
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type Ref;
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}
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impl<'a, T: 'a> MakeRef<'a> for T {
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type Ref = &'a T;
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}
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pub trait MakeRef2 {
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type Ref2;
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}
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impl<'a, T: 'a> MakeRef2 for T {
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//~^ ERROR the lifetime parameter `'a` is not constrained
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type Ref2 = <T as MakeRef<'a>>::Ref;
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}
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fn foo() -> <String as MakeRef2>::Ref2 { &String::from("foo") }
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fn main() {
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println!("{}", foo());
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}
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