src/test/compile-fail/object-lifetime-default-mybox.rs


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46

// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

// Test a "pass-through" object-lifetime-default that produces errors.

#![allow(dead_code)]

trait SomeTrait {
    fn dummy(&self) { }
}

struct MyBox<T:?Sized> {
    r: Box<T>
}

fn deref<T>(ss: &T) -> T {
    // produces the type of a deref without worrying about whether a
    // move out would actually be legal
    loop { }
}

fn load0(ss: &MyBox<SomeTrait>) -> MyBox<SomeTrait> {
    deref(ss)
}

fn load1<'a,'b>(a: &'a MyBox<SomeTrait>,
                b: &'b MyBox<SomeTrait>)
                -> &'b MyBox<SomeTrait>
{
    a
      //~^ ERROR cannot infer
}

fn load2<'a>(ss: &MyBox<SomeTrait+'a>) -> MyBox<SomeTrait+'a> {
    load0(ss) //~ ERROR mismatched types
}

fn main() {
}