rust/src/test/compile-fail/regions-escape-via-trait-or-not.rs

// Copyright 2012 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 deref {
    fn get() -> int;
}

impl deref for &int {
    fn get() -> int {
        *self
    }
}

fn with<R:deref>(f: fn(x: &int) -> R) -> int {
    f(&3).get()
}

fn return_it() -> int {
    with(|o| o)
    //~^ ERROR reference is not valid outside of its lifetime
    //~^^ ERROR reference is not valid outside of its lifetime
    //~^^^ ERROR cannot infer an appropriate lifetime
}

fn main() {
    let x = return_it();
    debug!("foo=%d", x);
}