| // Copyright 2014 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. |
| |
| trait Dummy { fn dummy(&self); } |
| |
| fn foo1<'a:'b,'b>(x: &'a mut (Dummy+'a)) -> &'b mut (Dummy+'b) { |
| // Here, we are able to coerce |
| x |
| } |
| |
| fn foo2<'a:'b,'b>(x: &'b mut (Dummy+'a)) -> &'b mut (Dummy+'b) { |
| // Here, we are able to coerce |
| x |
| } |
| |
| fn foo3<'a,'b>(x: &'a mut Dummy) -> &'b mut Dummy { |
| // Without knowing 'a:'b, we can't coerce |
| x //~ ERROR lifetime bound not satisfied |
| //~^ ERROR cannot infer an appropriate lifetime |
| } |
| |
| struct Wrapper<T>(T); |
| fn foo4<'a:'b,'b>(x: Wrapper<&'a mut Dummy>) -> Wrapper<&'b mut Dummy> { |
| // We can't coerce because it is packed in `Wrapper` |
| x //~ ERROR mismatched types |
| } |
| |
| fn main() {} |
