// 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 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. // Tests that callees correctly infer an ordering between free regions // that appear in their parameter list. See also // regions-free-region-ordering-caller.rs fn ordering1<'a, 'b>(x: &'a &'b uint) -> &'a uint { // It is safe to assume that 'a <= 'b due to the type of x let y: &'b uint = &**x; return y; } fn ordering2<'a, 'b>(x: &'a &'b uint, y: &'a uint) -> &'b uint { // However, it is not safe to assume that 'b <= 'a &*y //~ ERROR cannot infer an appropriate lifetime } fn ordering3<'a, 'b>(x: &'a uint, y: &'b uint) -> &'a &'b uint { // Do not infer an ordering from the return value. let z: &'b uint = &*x; //~^ ERROR cannot infer an appropriate lifetime due to conflicting requirements fail!(); } fn ordering4<'a, 'b>(a: &'a uint, b: &'b uint, x: &fn(&'a &'b uint)) { let z: Option<&'a &'b uint> = None; } fn main() {}