1 // Copyright 2012 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 // Tests that callees correctly infer an ordering between free regions
12 // that appear in their parameter list. See also
13 // regions-free-region-ordering-caller.rs
15 fn ordering1<'a, 'b>(x: &'a &'b usize) -> &'a usize {
16 // It is safe to assume that 'a <= 'b due to the type of x
17 let y: &'b usize = &**x;
21 fn ordering2<'a, 'b>(x: &'a &'b usize, y: &'a usize) -> &'b usize {
22 // However, it is not safe to assume that 'b <= 'a
23 &*y //~ ERROR 23:5: 23:8: lifetime mismatch [E0623]
26 fn ordering3<'a, 'b>(x: &'a usize, y: &'b usize) -> &'a &'b usize {
27 // Do not infer an ordering from the return value.
28 let z: &'b usize = &*x;
29 //~^ ERROR 28:24: 28:27: lifetime mismatch [E0623]
33 // see regions-free-region-ordering-callee-4.rs
35 fn ordering5<'a, 'b>(a: &'a usize, b: &'b usize, x: Option<&'a &'b usize>) {
36 let z: Option<&'a &'b usize> = None;