38 lines
987 B
Rust
38 lines
987 B
Rust
// 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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use std::fmt;
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pub trait MethodType {
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type GetProp: ?Sized;
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}
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pub struct MTFn;
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impl<'a> MethodType for MTFn { //~ ERROR E0207
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//~| NOTE unconstrained lifetime parameter
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type GetProp = fmt::Debug + 'a;
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}
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fn bad(a: Box<<MTFn as MethodType>::GetProp>) -> Box<fmt::Debug+'static> {
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a
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}
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fn dangling(a: &str) -> Box<fmt::Debug> {
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bad(Box::new(a))
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}
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fn main() {
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let mut s = "hello".to_string();
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let x = dangling(&s);
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s = String::new();
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println!("{:?}", x);
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}
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